Air Conditioning - Need to design/install complete HVAC package

Hi - well the time has come where I have decided to go ahead and install my own HVAC with heat, cooling and humidity control. Funniliy enought tis is the one thing that 2 years ago I said I would not do myself and just get somebody to come in and do it. Wel it turns out that after 4 contractors have come to take a look at it - and I have not had a single quote back. The only reason I can think of is because the house is a rancher with a fuly finished basement and I want both areas to be controlled independently.

So my question - who knows:

#1: Any good reading books (much like the taunton series 'For pros by pros' on HVAC design, concepts, whats what and how to install (basically HVAC DIY for dummies for complete new installs)

#2: Any good resources for technical help in making sure I choose the right seer and ton unit and help on placement of ducts (inlets and outlets).

I am entirely new to HVAC but like I said - the time has come to do it myself.. I am an extremely handy person and this does not scare me - what scares me is making the right choices..

Any help and guidance would be appreciated.

Thanks

Wayne

Well design is only part of the problem. Installation is very important. Start by doing a Manual J and D on the home. Then all you have to do is get the duct made, put it together, spot your holes, cut your holes, put in your spin-ins, put the duct together. insulated it, hang it, spot and cut for the registers, install boots the run the run outs, and insulate. Then we can start on the return. Then we can set the AHU, run line set, set outdoor unit?, then run low voltage and main power.

airman - I get what you are saying. My interpretation is this 'boy its a lot of work are you sure you should take this on given your lack of experience'. All too true - and my response will not be 'How hard can it be?' - but ok I get it - so now how do I make it work and properly because that is my only choice. The odds of 4 HVAC guys coming out to look at the house (none measuring the rooms to do a proper load calc - which you need for a J and or a D I am sure) and only one presenting me with a basic quote (of $17k - and that is with me ripping the floors up so they can drop the duct in and then me responsible for closing it all back up). Maybe in my area demand is greater than supply - sorry but I just don't have 17k to drop into this house that will only increase in value by 5k if I do based on the one and only quote I can get.

So here is what I have found so far - HVAC Calc sells a software program for the home owner and professional. The only diference between the pro and harry home owner version is that the home owner only lasts for 2 months. You can run it against as many homes as you want for 2 monthshttp://www.hvaccomputer.com

So now what I need is a book I can buy that helps me understand what the hell I am supposed to be doing. There is a service from Ductworks http://www.ductworks.net and they help you by doing the load calcs and design work for you for a fee of $350 and they also sell all the components so you potentially go that route. I am going to run the hvac calc even if just for piece of mind but any resources from anybody would be appreciated.

Wayne

You will attain the crown of King of DIY'ers if you don't go NUTZ! :wall: How did that place get built in the first place without ducts?:coffee:

I hope you've had better luck getting help since you posted this. It looks like all you'll get here is hvac contractors encouraging you to pay ridiculous money to their buddies.

Why even bother responding if all you're going to do is tell the poster to go pound sand?

This is just one more "profession" where they're trying to make it all but impossible for someone to do it themselves under the auspices of "it's too complicated for a dumb homeowner."

I have all summer to install something, I don't need to get it done in a few days which is where the experience really helps.

Hold on there vtoddball, like Jay's signiture says "If you can do it We can help".

Wayne is talking about a very, very major DIY. Heck it took me 10 or 12 hours to change just my indoor and outdoor unit by my self, and then another hour to get the charge right a week later. I had to measure total line set length and add 13 ounces of R-22.

Wayne

If your putting in a packaged unit your ahead of the game. If your looking at a split system you'll have to get EPA certified to work with refrigerants and face a very large learning curve and spend a few grand on the correct tool to do the job correctly. And keep in mind you'll be buying tools you'll need once.

Nothing ticks me off more than lugging tools up to a roof and I only need some of them for one thing and it takes 5 minutes for them to do it.

Your finished basement will probably need to be partially unfinished, and then refinished after the install. And as Airman said the duct work will be a major pain.

Since your a home owner who is going to sell stuff to you? Most supply houses only sell to contractors.

As mentioned before, youl'll be spending alot of money for tools you'll only need once.

Basically I think if you DIY this it will cost much more than 17Grand.

So all that said, my advice to for you to find a helper. You see HVAC trucks around town, start asking the guys in work uniforms if they do side work.

If you find the right person you'll get the benifit of not having to buy a bunch of tools and perhaps someone who knows his craft. And may have friends who need extra money for times when a two man crew is too small.

forgot this, you may want to watch these videos:

http://www.energyvideos.com/bldvid.php?P=CA&A=5&S=hva

OK so I also selected to do my own HVAC and here is my story for what it’s worth. First I found it very hard to find a contractor around my area that would do the job I wanted, each time someone came to look and price the job I got a 'Do it my way or I don’t want to know' or they just did not come back with the quote as they said they would. BTW This was for a finished basement I was working on, the 1st and 2nd floors already have HVAC, and the house is approx. 4 yrs old.

Now I understand there can be a LOT of time and calculations to correctly work out and size a system, I am not going to suggest anyone can do this BUT working with the local inspector, turns out some basic rule of thumb is all that is needed. AND to be honest none of the contactors expect 1 worked out how many windows, doors, type of walls insulation etc. this job had and how it would affect the sizing. AND his design and quote was the crazy one of them all, wanting me to spend $15k and tie it in with the upstairs units :eek: Also worth noting is the units already in the house only just do the job so I dont think much 'planning or design' took place for them!

So for my basement, 1100 SqFt I know I needed between 1.5 and 2 TON heat pump system (I have a lot of extra heat due to 1/3 of the space being a home theater and lots of heat from the electronics. I also have a full walk out basement and get a lot of sun/heat which may not be common to a lot of basement this size where a 1.5 unit should be more than enough.

So using flex duct I was able to take 2 main runs and break it down into 8", 6" and a 4" drops to meet the cfm required for each room and totaled the capacity of the AH unit.
I found some very good sizing info on the internet which was validated by the inspector who told me for this area (NC) they look to make sure you have the right size and R rating duct and the room can be heated to 68oF. In fact the inspector was very helpful, mostly as I was a homeowner doing my own work.

Now for the tough part, getting someone to hook up the lines :( As the contactors make their money from crazy mark up of the hardware, you may find it VERY hard to find anyone who will work for parts and labor to make the final connections. Also I found out that the manufacture may not give you the warranty BUT some of the resellers honor that warranty themselves. I can tell you where I got my stuff from if you’re interested but a simple Google search should work.

Let me know if I can help more by sharing my experiences.
Mark.

Good link to info and sizing doc...

http://www.alpinehomeair.com/related/Ductwork.pdf

http://www.southface.org/web/resources&services/publications/factsheets/2duct_q&a.pdf

Mark - thanks for the information.. I'll be looking that up and checking it out. I have decided to enter the King DIYer pageant this year and install it myself.. not for any other reason other than the fact that NOT ONE contractor done the work required to correctly calculate the load. As Mark says, windows, doors, room sizes and other factors. If I walked into a room in my profession and told a customer what was wrong with their systems without listening to them or even reviewing the history then how much faith would they have in me? Thats not the way I work - anally retentive and methodical, do the math then the planning then the work. I am not blanket swiping contractors I am just saying that in order to gain my trust for me to hand over a huge stack of money you better show me you are going to plan it properly because if you don't then how can I trust that you will do it properly?

To that end - if anybody has any useful info I would really appreciate it.

Thanks

Wayne

HVAC contractors love to give a bid

If they haven't, either they

1) see the installation as a nightmare, or

2) think they can't make an agreeable solution with the customer


There might need to be some major fixes besides just putting in a new unit?

Wayne,

I am not sure if I didn't see it or not, the home has nothing at all? (Furnace, A/C and ductwork)

Single story two story or... what type of home?

If the home and basement if finished, and has nothing, I can see why the other has run away.. As Oregon said, they may see this being a nighmare or they are going to run into a lot of hidden cost as the job starts.

wayne186

I have not had a single quote back. The only reason I can think of is because the house is a rancher with a fuly finished basement and I want both areas to be controlled independently.

only one presenting me with a basic quote (of $17k - and that is with me ripping the floors up so they can drop the duct in and then me responsible for closing it all back up).

I can see why no one came back here. Also why that one bid is high. I think it would cost less just to put one unit run in the attic . The other for just the basement in the basement. might be able to just box the duct and registers throw out from there. Even if you put it in your self . You still need a EPA tech to vacuum and put the freon in . Id say you might find some one that will do it for Time/Mat. Thats about the only way we would do it

HI, Wayne.

There are alot of things to consider if you do decide to do this yourself. First is expense, in order to do the job properly you will need to get the right tools, ie; torch kit, multi meter, vaccuum pump, manifold and various tools. If you don't all ready have them you may be able to pick them up cheap at a pawn shop. If not you can expect to spend aprox. $1500 just for the tools. Second, is the equipment itself. While you can buy the equipment on-line usually you will void any warranty if it is not installed by a licenced technician. Also in regards to the equipment, you will need to determin how high of a seer (efficency) rating you want, anything more than 16 seer and it will take much longer to see any savings. Also you may be able to get a rebate from your electric company depending on how high a seer rating you install.Another thing to consider is what brand of equipment to buy. Be wary of the "name brands" ie: trane, carrier, etc. They are all good units but you pay for the name not just upfront but also when you need to get it fixed. Third is installation, if you do do it yourself, make sure to read all the installation instructions carefully, after all you will have spent several thousand dollars on the equipment and would not want to damage it or yourself while putting it in. As for getting help, as jarredsdad said you could see if an a/c installers helper does side work. If you get one, ask him how long he has been in the business and how long he has been with the company he is with. If it is less than five years to either question be wary, as they may not have as much experience as you would like to avoid any problems. Finally on sizing the equipment the load calc should be pretty close but make sure it takes into account your location as well as which direction the windows face and number of occupants as well as if your house is elevated and how much insulation if any you have. If you decide not to do it yourself a good way to find a contractor is to call a local a/c supply house and ask for a few recomendations, most are happy to help. Hope this will help you some.

I'd like to add, to do it right you'll also need:
oxyacetyline torch set
brazing skill

Hello Wayne,
I wonder if you DIY after all.
I'm about to get into this project in a small scale.
Second floor, two rooms + hall and bathroom. about 700sf
heating and air condition.

If you have any information (same questions you asked, books, websites. videos...)

Thanks
DH

DH - I did go DIY in the end... I am close to putting an order in for all of the materials and with that I get all the support and help I need from the suppliers plus they done the HAC load calcs for me - I double checked :coffee: using a nice tool sent to me by a nice man on this forum :-) :mask: name with-held to protect the guilty - thanks pops!

Go with http://www.ductworks.net and they will give you excellent service.

Good luck

Okey dokey - so the results are in ladies and gentlemen. I have all of the load calcs completed by both the designer and I also ran them myself to 'double check' - not that I am an untrusting soul - I just wanted to do it for my own piece of mind too. We both came up with the same sized units, now with the sizing completed and the duct work design done.. I have questions.. and lots of them - but lets start with the first few..

I have a choice between Goodman and Ruud. What would you choose? Both units are the same sizing, here are the package details. I did include air filter as the cost between Ruud and Goodman is significant enough to mention.- not including ductwork, humidifiers, thermostats and dampers etc:

Goodman 4 ton 16 seer conditioner unit model#SSX160481, 3.5 ton variable speed air handler model#AEPF426016 & 15KW heat kit (51'000 BTU) model#HKR15c.

RUUD 4 ton 16 seer conditioner unit model#UPRL048JEZ, 4 ton 16 seer Hi-Efficiency air handler R-410a model#UHPL048 & 15Kw 208/240/1/60 electric heat kit model#RXBH-17A15J.

There is a cost variation of $1'167.14 between the two systems, RUUD being the highest. Can anybody give me any insight as to why they would spend the extra money on a RUUD versus a Goodman? I have yet to speak to the designer and find out things like warranty terms etc as I got the quote late friday night - so I figure I would put it to all my helpful friends on the diy forum first ;)

Next question: I am going to do three zones in the building because I want to save energy. I also want my thermostat to have a web based interface so that I can control the temperature and humidity even if I am away from the home. I am a techy and all things in my home have to connect to my network.. forgive me for my sins :-) So what I am looking for is a thermostat that can control three zones, the system is a 2 stage design and will have a humidifier (I hate static electricity which is potentially a side effect of electric heat). I have been looking at the prolifix line and they seem to be so far the best option. Does anybody know of any other products out there? I would prefer it if I could have only one thermostat (these puppies run around $500 each so buying 3 would be silly money just to satisfy my retarded desires). Can any thermostat that you know of have at least 2 remote sensor probes (place one in each of the secondary zones and the thermostat be placed in the primary zone).. have these zones wired up to dry contacts which open and close the dampers as demanded by the temperature. Humidity control is only important in the primary zone! The thermostat I was looking at is the prolifix TM250 which can do this but I need to speak to the manufacturer and find out if they can do it all with one thermostat or if I have to buy three.

Lots more questions to come... but this is moving forward now and I am getting real excited about earning that 'King of DIY'ers' award :-)

thanks - Wayne

Your not finished yet!!! Get off your Butt. Just kidding.;)

Lost the link to your project, didn't see it here maybe you sent it in a PM or email. Post it so we can see the progress.

Tall order here my friend. I would not go Goodman or Ruud. Lennox, Carrier, Trane.

Zoning from Lennox (Honeywell). Dampers, very important to use powered open spring closed. Powering a damper closed keeps power on the motor when heating/cooling is not needed. Should only power motor when you need it open.

1/2 hour later my Wife's "be ready in a minute" is up and need to go to Lowes.

You've provided enough info to be dangerous. I'll look at brands I've suggested and provide alternatives and zoning info later, with web based possability.

Can't think of the name right now, but I know of and have worked with a company in FLA that makes controls (networkable) that will allow remote control of the entire house. Yes, even the kitchen sink.

Pops;)

Or this outfit?

http://www.johnsoncontrols.com/publish/us/en/products/building_efficiency/products/hvac.html

Those boys have been busy, much more product offerings. Can connect unlimited units together with two wires and net interface at the end.

Contact us pages shows Brian (son and brains) as Pres, talked with him many times on land line. John (Brians Dad) as VP marketing, met him - nice guy, came out of retirement to help Brian get off the ground.

Check out the site, if you want to finish the house like George Jetson's thais is where to go.

Static electricity comes from low humidity not elec heat.

Incase your wondering, back from Lowes $370 in 2 hours and ceiling fans to install. Mulch to spread, etc..

Well, to be honest, it's hot as heck now so one fan will go in today, other is attic work maybe in the morning. Mulch after sun down. So I maybe back. ;)

Pops - nice to hear that you have time to go to lowes and sit on the sofa twiddling yer bollocks while you wait for the good lady to do her hair in preperation for bumping into all those semi handsome fellows in the store - I say semi handsome because real men and the more handsome ones go to home depot :blah: What in the world are you doing to take all day to install a ceiling fan anyway?? Heck if I took that long with my projects I would still be working on the footings :D

So - the link to the projects.. apparently it is frowned upon to have links in your signature and that was the link to my personal web page showing all the projects.. but (and I hope I do not get an infraction for this.. because I am not selling anything - just showing what is happening on my home projects).. The photos can be seen at http://www.wayne186.com/Photo_album/Building%20Projects/Barn%20Building/index.html and yes - this is for the barn.. I have aborted the house hvac install for now and decided to do it in the barn instead.. but the house is next.
As for the selfbuild side of things - go to http://www.wayne186.com/selfbuild - this site is undergoing a major revamp when I am not outside pounding nails so things may look a bit funky now and again.

So no to Ruud or Goodman then? Hmmmm... methinks I am going to have to check back with my friendly designer and see what he has to say and what else in on offer. But I did read earlier on in this thread that trane etc are big brand names that can cost more just for the name?

Who knows where we can get an independant review on HVAC products? You know like Cnet.com does for anything electronic..

I will take note of the spring closed and powered open factor for the dampers and also at the controls. Come the end of this I will be sure to post all the specs and other useful info for those of you that are also seeking the Kin DIY'er awards :-) But this year... that baby is MINE... all MINE I tell you :-)

I did put the master fan in since there was already a secure box that can handle a fan.

I let Mom take her time because I was answering your post.

The second fan will be more involed as I have to add the box and add the power, in the attic.

Wife says I'm grammatically incorrect, too many comma's (and miss spelled grammatically a few times, gotta love her).

She's sitting next to me making fun of my spelling too.

Call it personal preferance but I've never liked Rheem or Ruud. Goodman, I changed an outdoor unit for a townhouse we rented and the comp didn't last a year. I did the changeout, I know it was correct and I had to change a comp under warranty. Not in my house will I have one of them.

Wayne, it's your place and do what you want. I can tell you I work on Lennox units 40 odd years old (actually haven't been over ther for a while as nothing is broke).

You know what size system you need, don't be to hasty in selecting the brand system you will put in.

Also, remember your asking for web based controls. Takes time to think and rethink that stuff. Don't jump yet.


I'll be back.

I'm with Wayne. MOST contracter want to rape you on an hvac system. I owned a house and got 3 contracters to come out. Only 1 guy sent me an estimate of $8,000 for just a forced hot air system. No AC. No modulating furnace. He wanted $3,500 extra for the AC. Total $11,500. None of the contracters seemed too excited to do the job. So I basically told them to go and you know what and do it myself.
I purchased a RUUD modulating furnace,AC split system,modulating thermostat,duct work and everything to finish the job for under 4,000!! American dollars. Paid someone $200 to test the lineset and evacuate it.
So listen guys (contracters)I know you guys have to eat and take care of your families but how can you justify charging someone(in my case) around $8,000 labor for a job that would take 3 days? Anyone? Do I hear crickets?:coffee:

I think if you read through the thread you will find that we can hear both sides of the story here, I personally have no beef with anybody giving me a high dollar quote and I really do understand it.. with the millions of people prepared to part with their american dollars quite happily - why would a contractor come to yours or my house and do a much harder job for the same fair price. It is a sad but true fact that we get to choose what we want to do when we can, 'cherry picking' I believe is what it is called.. we all do it. I personally go to the supermarket and cherry pick my way through the best tomatoes.. same thing but just on a much grander scale. I am sure you do too.. now the beauty of living in america is that we have the freedom of choice. You can choose to get somebody else to do it and pay through the nose if your cherry is not so sweet as the others or you can come here and learn what you need to know to do it yourself.. with the aid of those same contractors for which again.. I have no beef.

I think this thread has long since moved on from bitterness and resentment - for I am enlightened and truly appreciate the wise words of wisdom from those that have a passion for their profession and helping us mere mortals attain those crowns.. for those are the guys (and girls ) that I believe would do my load calcs before giving me the quote. So it is official - lets agree that we all cherry pick when we can and forgive and forget.. no more contractor bashing if you please for we are all guilty of much the same thing are we not :-)

So is Wayne the guy with long hair or short?

Did some digging this morning. Lennox makes a 410A unit with pretty good performance ratings. This 4 ton doesn't drop down to 3 ton performance until 35 degrees outdoot temp. Look at page 73 http://tech.lennoxintl.com/PDFs/ehb_xp15_rtgs_0704.pdf

Honeywell has a zone system with "Telephone" access.
http://customer.honeywell.com/techlit/pdf/70-0000s/70-0851.pdf

I think if you really want net access, You should call John or Brian at MCS.

Just wondering about water. Can you install a well that will provide 3gpm for each ton of heating and cooling? Or since you have digging tools, enough space available for trenches? 150 foot, 8 feet deep per ton, spaced at least 12 feet apart? Vertical would be 12 feet apart and 200 feet straight down.

GeoThermal packaged units would be true plug and play DIY.

Reminds me of ole` Scott Adams a welder who built his own house with Geothermal closed loop.

Just imagine a beautiful 2 story brick house and the first thing you notice upon entering the crawl space are the huge 16 inch steel I beams the house sits on.

Almost forgot about him, a true DIY masterpiece.

Wayne is the short haired more dashing looking chap :-) Of course a regular shopper in Home Depot too.. :-)

So here is the latest digging... I done some research and found that ONLY registered HVAC installers can go out and buy units like Trane, Carrier and all of those type units. The guy I am working with can only sell Goodman and Ruud because they will allow their distributors to sell online, I do have the option of buying a 3 year old carrier 4 ton unit but this is not going to come with a warranty because it will be installed by yours truly who is evidently not a registered HVAC chap. Looks like I will save $500 if I went with the used unit - hardly seems worth it considering the nightmares that may unfold.

It does not seem fair to me that the manufacturers would place such a crimp on the DIY market and refuse to sell to the general public but then I have never been one to not rock a boat or two. Of course I would love to buy the best brand out there - but if nobody is willing to sell it to me then it looks like I have no choice.

For those that are not faint of heart then - and going the distance on your own.. these are the things that I have learned so far.

#1: Use this forum.. super helpful people and very constructive advice.
#2: Find a book or something to 'edumacate' yourself.. the company I am working with on my design does a good one http://www.ductworks.net/xcart/product.php?productid=541&cat=0&page=1&featured
#3: Do your load calculations to determine a correctly sized unit
#4: Get somebody to design your system that specializes in this, don't try and do this yourself! Ductworks have designed mine.
#5: Try to have a full materials sheet included in your design and put this out to other companies for supply of materials only
#6: Make sure you have at least two people in your back pocket who would be prepared to complete the final hookup and charging of the unit for you. This is very important because you will not be able to legally do it yourself, the tools cost a lot of money and without it you may as well have bolted a very expensive door stop to the side of the house :-)

Pops - on the geotherm stuff.. I have lots of room for trenches and I could do a lot of that myself.. but I think for this project (the barn) I will be sticking with the norm.. however I am going geotherm, ICF and solar in the new house I will be building after I have rested up from building this bleeding barn.. I have promised myself a year free of hammers and nails after this project so I can get outside and mow the fields and relax to enjoy life again :-)

Sooooooo, I've read every post in this thread and have come to the conclusion that I still don't know if I'm up to the challenge of installing my own HVAC. GI2 I'm at the very start of finishing my basement myself and I believe the HVAC to be the biggest hurdle in accomplishing the whole project on my own.

This is why I'm considering it: I'm decent, knowledgeable, and creative enough with woodworking, drywall, framing, painting, electrical, etc. to give it a go. I'm thorough and willing to properly calculate loads, draw designs, etc. to do it right the first time. I have the time. Most importantly, I'm cheap. If I can save several thousand dollars doing it myself, then I'm good with that.

This is why I'm not considering it: I know next to nothing about HVACs. :cheshire: I don't know a lot of the terminology used in here. There are enough warnings out there and in this forum to scare me. Whether it's so skilled technicians keep their jobs, there are real hazards to the work, or the cost and time are not worth it, I do take notice! It may be that after the time and cost of the tools to complete the project, it's not really much of a savings. Also, maybe it just really takes a lot of skill that I don't have to do this work.

I'm really surprised at some of the estimates that everyone is throwing around in here. My home is fairly new, has about 1,800 sq ft unfinished basement with about 1/2 of the walls with windows. It is similar to other homes in my neighborhood that have recently had basements finished. Most quotes they got for a new HVAC unit is around $4 - $5K. I just don't understand the $15k numbers, even with the added hastle of working in finished areas.

To Wayne, I don't mean this to sound negative. More like a question. I'm surprised you haven't already finished the install. Is it that you were in no hurry and have just worked on it here and there over the past year, or is it that it's just too involved to get it done quickly for the do-it-yourselfer? I'd really like to know what your thoughts are about that.

Anyway, I'd sure like to read others like me who HAVE done it themselves. How did it go and was it worth it?

Thanks!

Well.. you ask so I shall tell.. I am sure others have been wondering how come I have taken so long to do this myself. When I originally started this thread it was intended for my house that I currently live in, as time has gone by I started to build a barn myself and it has distracted me from putting the AC in the house. First I had to design it all and then build materials lists and then clearing out the tree's and then I got to start building it. The barn is a 7500sq ft project and I have just finished putting the roof on it: it has a 50x50 workshop 20ft tall, 9 horse stalls at 12ft x 12ft, a music recording studio 12ft x 24ft, a rest area for the horsey people with a restroom 12ft x 24ft and an apartment of 24ft x 60ft. Only the rest area, music studio and apartment require HVAC and so along the way I have continued my HVAC research and simply adapted it for the barn. All the things I learn will be applied in the install at the house when I have finally finished the barn.

I have found what will work for me and that is a company that will remove the technical element from me and design the system including duct sizing and confirm load calcs. They are also on the end of the phone for help and I have a guy lined up to do the charging which is the part where you need all those expensive tools.

I understand your reservations about installing yourself - but along the way I have met some really good people and am fast gaining a new skill to add to my list of DIY'ers :-) The first thing I would say to you is don't be scared! There are a lot of nay sayers out there and surprisingly a lot of them in HVAC.. it is not rocket science! and people on here will help you - especially if you do your own due diligence and learn a bit about it.. if you don't understand some of the terminology then google it or ask us.. for me no question is too stupid..

What I would do in your situation is get some quotes and watch out for the ones that don't do the load calcs, then do your own load calcs and maybe speak to ductworks or another company that will do the design for you and ask them to just run a quick analysis of the space you are trying to install a hvac for and get a ball park figure from them for materials cost.. then add the cost of how much somebody would cost you to charge the system and there you have your diferrence.. if you can live with paying somebody the diference then go for it - but if you are cheap like me and like to try new things then we will be hearing lots more from you :-)

Good Luck

Hello Hrjrkr,

Question for you since you seem to have actually done it yourself.

I’m a DIYer, pretty much remodeled my whole house. Worked in a factory as a general mechanic when I was younger, so I’m a quite a jack of all trades.

My home already has the whole central air con system set up, compressor on the outside, the air handler on the inside, duct work, tubing, electrical, all set up. However, the system is old and needs replacing. Quotes are quite expensive.

I’m pretty sure I can do it myself. Air handler - connect to gas, vent, exhaust, drain, electrical, seems easy. The copper tubes (from the outside) seem to be standard size with compression fittings. No problem.

Compressor out side seems straight forward too, single phase 220v electrical, thermostat remote wire, seems easy too. (remember, it's all already there)

However here is the detailed question I have:

When I connect the compression fittings from the high and low copper lines on to the new compressor (usually near the bottom corner of the compressor) and make sure it is nice and tight with a good seal, do I then unscrew the allen wrench plugs which are located inside the valve right next to the compression fittings? if so, how many turns? Until I hear the freon runs into the tubing?

OR, I've read on this forum, more then once, this is when you have to get the Technician out and have the evac and fill the system. If that's the case, then would it be correct to say that a new compressor does not come with freon in it?

If someone can clarify this step a bit, I would appreciate it! Thanks!!

I'm not Hrjrkr but I'll reply anyway.

Several years ago, maybe a dozen, I forget exactly, the Federal Government via the Environmental Protection Agency enacted rules concerning the sale, use and handling of Chlorinated Fluorocarbon refrigerants. Essentially they made it unlawful for anyone other than an EPA tested and certified person to buy, use or handle said refrigerants. The test is about fifty bucks as I recall but the equipment to deal with all the regulations will set you back literally thousands.

The end result is that you, as an uncertified individual may NOT deal with any part of the refrigerant carrying parts of the unit. Violation of the rules makes you liable for fine or imprisonment. I think the fine is $10,000 but it could be more.

I could answer some of your other questions but I doubt that it makes any difference after what I previously wrote.

The copper tubes (from the outside) seem to be standard size with compression fittings.



When I connect the compression fittings from the high and low copper lines on to the new compressor (usually near the bottom corner of the compressor) and make sure it is nice and tight with a good seal, do I then unscrew the allen wrench plugs which are located inside the valve right next to the compression fittings? if so, how many turns? Until I hear the freon runs into the tubing?

First of all, Compression fittings are NOT used with A/C system. They are brazed.

You should not be messing with the system anyway since must be certified by the EPA to do this... And FYI, the steps you mention above is missing A LOT must do before you even crack open the valves.

I've seen people come back on here or another board wishing they did not do the DIY steps since it end up costing them more after the fact they made an error on their end.

I am for DIY, but major equipment like this should be left with the Pro. I used to be in the fields 15 years ago, and I did not do my equipement change out myself.. I hired the pro knowing I will have warranty back up.

Jay & Furd, I am sure you mean well chaps but 3 paragraphs on the rules and regs and how the EPA has tied your hands told philip nothing - except that the fittings are brazed and not compression.. come on guys.. :wall: we get it and we have heard the arguments throughout this post! However - something needs explaining and if you don't want to do that then don't say anything. This is a DIY forum - we don't care about government rules because they suck, we care about doing the job ourselves, on a budget and doing it right which is why we ask all these annoying questions.

So what does philip have to do? From all that I know - the unit comes empty and materials/tools to do the fill are 'best left to the pro' so does he hook those lines up like he said, leave the allen key bolts alone and then call harry the hvac guy?

By the way philip, you may want to call first and shop around for a price on somebody filling for you. You may find they charge you so much that you may as well have got them to fit the units?

Okay, Wayne, I'll answer the questions.

When I connect the compression fittings from the high and low copper lines on to the new compressor (usually near the bottom corner of the compressor) and make sure it is nice and tight with a good seal, do I then unscrew the allen wrench plugs which are located inside the valve right next to the compression fittings? if so, how many turns? Until I hear the freon runs into the tubing?

OR, I've read on this forum, more then once, this is when you have to get the Technician out and have the evac and fill the system. If that's the case, then would it be correct to say that a new compressor does not come with freon in it?

First, you do NOT have "compression fittings" on your unit, you have flared fittings. Unless you have more than a little bit of experience in making flares, along with a professional flaring tool (NOT a HD $5 tool made in China) and experience in actually "making up" the joint you will more than likely have a leaking fitting. It may not be a big leak but it WILL leak and you will lose the refrigerant.

Second, refrigeration valves have a backseat. If you do not understand that term then you have no business opening any refrigeration valves, regardless of the legality.

Third, no, refrigeration compressors do NOT come with a refrigerant charge. Perhaps you are confusing the compressor with the condensing unit and if this is so then that is one more reason for you to NOT try DIYing the installation.

Finally, whether or not someone believes that the law (any law) is bogus is not sufficient for me to advise anyone on how to violate the law. It's called ETHICS and even if this board did not have a stated prohibition against posting such information (see the "stickies" at the top of the page) my personal ethics would preclude me from doing anything that would give someone else the knowledge to violate the law. If Philip, or anyone else, chooses to violate any laws there are plenty of other resources besides this particular forum that are available.

Makes me think of a gaggle of bickering old women.

Hate to say it but I can agree with Wayne, Jay, and Furd on different levels.

Wayne, you know the rules here. We agreed when we signed up not to offer advice or give directions as to sealed system repairs in the "public" forums.

Furd and Jay are just adhering to the promise made.

One of the chief reasons not to provide advice of this type is to prevent someone else from trying the same thing just because they read it in some thread or another.

The number one reason (beyond the obvious leagal) is that people in most cases do not follow directions.

I remember I sent someone a software program and it took him months to get it installed. I kept sending the same directions, he didn't follow them and kept trying his way. After months of trying He finally did what I said the way I said and had a working program.

Now, with that in mind, you think it safe to tell someone how to work with a refrigerant that boils from a gas to liquid at -22 degrees (or whatever it is)?

In Phil's case, he said he had an old unit. If old enough it could very well have flare connections which these days are only used mainly on mini splits.

I would think the best advice for him is to try and partner with a pro to come in at certain phases of his project.

Recover, braze, pressure test, evacuate, charge, and check out.

I see no reason why he couldn't get new equipment from this partner, do all the grunt work himself and have the pro come in (and get paid) only when needed.

Would of course take longer, but maybe cheaper. And He would know that He, basically, did it himself.

Funny how there are so many nay sayers out there. I'm pretty sure they are the same A/C contractors that is scared of losing revenue. Leave it to the "Pros" and let them "calculate" the amount of freon needed.

Funny thing is, I've observed several "Pros" do this. It's usually a over weight, smelly dude with a big butt crack, carrying a tank of Freon and a set of gauges. They recharge until the gauges are in the "normal" range, then they are done. Not so hard.

The only question I have is the "fitting" between the cooper pipes and the unit. Flared or brazed, how hard can it be?

I've got a masters degree, I've remodeled my whole house by myself, i have four cars in my driveway that I've rebuilt from bumper to bumper. I own a 30000 sq ft factory full of machinery that I work on and fix every day. I think I can handle replacing my AC unit.

I thank those who actually tried to help!

If you get me a set of those gauges that have a normal area on the gauge I would pay you for them. I have been looking for them all over the place and can't find them.

Gee Phil, only a month and a half between posts. I know going to those Obama rallies is taxing on the free time, but I thought this was important.

After this last post, I say go ahead and do it.

Go out and get your EPA cert. Go buy a recovery machine, vac pump, gauges, refrigerant, nitrogen, torch (you may already have one), nitrogen regulator, vacuum gauge, strap on thermometers for piping, sling thermometer to get web-bulb temp, and at least 5 things I've forgotten.

I'm not trying to be sarcastic here.

Getting your EPA cert is easy. Buying all the stuff you need after that is easier still.

I do feel that you are missing the point HERE.

We (speaking of "pros") promised not to offer any advice as to sealed system repairs. Which we adhere to, like it or not. There are other forums out there that will discuss such matters.

Getting the government cert and being licensed to carry around refrigerant with your butt crack hanging out is easy.

Actually knowing what to do with the gauges, thermometers, etc is not.

There are those of us pros who know with 90% certainty what is wrong just by the sound of a unit. Which equates to less billed time troubleshooting.

The water is warm Phil, Jump in.

P.S. If it were not for the crack people wouldn't know I even had a butt.

Now that right there was funny jarredsdad - but honestly.. might I suggest a belt for your trousers when you come to fill my system :-)

Phil - I am with these guys when it comes to filling your system.. if there is one thing I have learned in the process of building my goliath.. there are some things that are best left to people who know what they are doing and another fine reason is because all of those tools will cost you a lot more to buy than just calling harry the hvac and getting him to do the fill.. much safer too. Some people on here are Naysayers I agree - but collectively we get good common sense advice from guys in the field on here.

Be safe with whatever you decide to do.

I still would like to have those gages! No more sub cooling checks! No more super heat! It would save me a lot of time. JD can you get these in Cville!

What a shame a 10 month thread reduced from talking smack to talking crack, sorry I couldn't pass that one up.
I don't care where yur from that there's funny.

Only gauges I have with a "normal range" are for 134A. Bought it because I couldn't find the auto adapters. Which I did find, once I used the new gauge and couldn't return it.

Why is there so much anger here? It's not like there is only one air/con business in the world and I'm trying to take your revenue away. I think people need to relax and take it easy!

Haha, and I do agree with most of you. I'd probably do all the heavy lifting myself and hire the butt crack guy for the final connection and final refill/recharge.

People, please don't be so :madhell: and go have a ice cold beer! Beer 4U2

By the way, It's been a month and a half because it's not that important, it's only an a/c unit! I live in Los Angeles, I can open my window and use a fan and achieve almost the same result! Hahahaha It's almost November now. hmmmmmm.... I might not even think about it until next summer!

Good idea. If your lucky the Dems will have the White House, Senate, and House and your repair will be 3 times as much as if you had done it now. ;)

I'm not angry and I don't see any other respondent in this thread that seems to be angry, at least not to anyone posting.

I learned the hands-on part of refrigeration work when I was in my early twenties. We didn't have the laws way back then that exist today and so we didn't have to have much more than a halide torch and a manifold gauge set. More often than not we just used the compressor as a vacuum pump and purged the system with dry nitrogen until we thought it was good enough and then added the refrigerant. We'd purge to atmosphere or sometimes into a bucket of water so we could see the bubbles. It was pretty much a seat-of-the-pants operation. If a system lost a bit of refrigerant over the course of a year we simply added more until it ran satisfactorily. We didn't worry about SEER (because there was no such thing) or ozone depletion. Freon was cheap and so was electricity.

In my mid twenties I learned much more about the physics of refrigeration systems and the design of HVAC. I even designed a few systems and oversaw the installations. Since that time I have also learned that properly designed and installed systems are the exception rather than the norm. Residential cooling was still fairly new at that time, at least using central systems instead of window bangers. Even the popular do-it-yourself magazines often had articles on how to build your own window A/C units from an old belt-driven refrigerator condensing unit.

In the last ten, fifteen or twenty years the dangers of depleting the earth's ozone layer have come to light and it also became common knowledge that the chlorinated fluorocarbon refrigerants that we all thought were so safe were likely a contributing factor in the depletion of the ozone layer. The result was laws such as we now have were implemented.

I'll admit that I am not fully convinced that the problem with the ozone layer is/was a direct result of the misuse (and misuse it was) of chlorinated fluorocarbon refrigerants and I am not convinced that the laws restricting their use need to be so draconian. But the plain fact is that the laws do need to be obeyed until such time (if ever) they are relaxed.

Alrighty then folks... well I just bloody did it! Today I finished installing the HVAC system that was designed for me by ductworks. It went smooth as silk (with a few stitches).. so I used the insulated ductboard on almost everything and I LOVE it! The small amount of tin knocking I had to do irritated me and normally bein such a cheap sod I am so glad I paid the extra money and worked with the insulated duct. It was so easy to put together and cut into for the takeoffs (ark at me I even sound like a HVAC exposed butt crack guy) :-)

So I have 3 zones controlled by 4 dampers (2 for the main upstairs zone and one for two seperate zones downstairs). I also have a static pressure damper to let air flow between the return duct and the supply plenum before the dampers that control the zones. I have a humidifier installed in the plenum and I have three proliphix NT150h thermostats to control it all. At some point I will put another post in here detailing all of the main parts and how I connected all the controls, dampers, electrical together. Right now I am feeling bewildered but I have faith in ductworks helping me through it and I have a real HVAC butt crack guy stood by ready to come and connect up the copper between the unit outside and the AHU, charge, check my handywork and do any fine tuning.

So right now I am a happy bunny. If anybody has done any multi zone work and using the proliphix controllers to control it all with the humidity system I sure would appreciate your input. My thought at the moment is that I somehow connect the thermostats to the dampers to open them and also connect all three thermostats to the ahu to turn on heat or cool and the humidifier? Of course this is my first stab and nothing will be connected until I have full understanding.

Thanks

Wayne

Alrighty then folks... well I just bloody did it! Today I finished installing the HVAC system that was designed for me by ductworks.

1) insulated duct board
2) 4 dampers
3) static pressure damper
4) humidifier
5) three proliphix NT150h thermostats
6) air handler unit
7) condenser unit

Thanks Wayne

Wayne, can you give us exact details on this equipment please?
thanks
Craig

being there is worth a thousand words but what you just explained sounds like trouble. If I understand you could have half of the basement calling for AC and the rest would dump into the return! Sounds like a frozen coil to me.

If I remember correctly this is for the garage/shop and not the house.

Why do you have 4 zones?

What is controlling the entire system?

Don't say you have tstats controlling a unit and a damper. That would be bad.

Echo Airman, frozen coil.

A little more info please.

Waynes website:Selfbuild (http://www.wayne186.com/selfbuild/)

I just spent way to much time reading this mesmerizing thread... wwooww. As I was looking in the mirror to see if my crack was showing a sound hit me ... like a peice of ice falling off a coil..

Whoa there boys.. whats with all the negative ice vibes :-)

Sorry it has taken me a while to get the answers to you but I have been out playing bob the builder.. this will not be my last post in this thread but I figure since you have all stuck with me for so long on this project I figured I should get the meat to you now and serve you all the veg in a little while.

So here is the equipment:

Goodman GSC130421 3.5 ton 13 seer AC conditioning unit
Goodman AEPF426016 Goodman 3.5 - 5 ton variable speed air handler
HKR15C 15Kw Heat Kit (51'000BTU)
Aprilaire by-pass humidifier

The dampers are all Honeywell and are as follows:

SPRD14 14" Pressure regulated damper (Bypass/Dump) which is connected above the plenum and connects the supply to the return.
ZD10x8 dampers - I have two of these for zone1
ZD12x8 damper for zone2
ZD16x8 damper for zone 3

The thermostats are all proliphix NT150h which are network capable with built in humidity, heat, cooling capability for systems with 2 stage heat/cool. I have three of these - one for each zone.

Now the tricky part has been integrating all of this together and that is where the Honeywell control panel comes into play.

It is a HZ322K TrueZone 3Z 2HT/2CL control panel. Each of the thermostats are wired into this, each of the zone dampers are also wired into this into their respective zones for damper control and the final connections are for the air handler. Now I hear lots of screams about freezing coils and again I am going to admit that I am no HVAC engineer (mainly in part because I can't show my butt crack for the fear of getting into the habit and pissing off lots of my customers.. lol) so being a logical kind of guy it took me a while to figure it all out but when I did it seems to make sense to me (feel free to offer your own advice or verdicts because as of yet this system is not doing any cooling) but there is also a device that I bought with the control panel and it is called a discharge air sensor. This is also wired into the control panel, it is physically installed inside the duct that connects the supply and return air but it is crucial that it be placed in an area where it can sense ambient temperature which must not be above the heat packs nor after the pressure damper. What this does is sense the air temperature in the connecting duct and determined by the variable I configure on the control panel will shut down the heat or cool if it detects that the temperature in here is higher or lower than that required.

Of course I am still learning, I have still got some work to do like wire up the humidifier and get someone in to connect the soft copper between the air handler and the condenser outside and fill the puppy up with the special gas that requires a special butt crack and gauge.. I am frequently referring back to all of the manuals and have certainly got some opinions about a lot of things in the HVAC world now which will be the veg part of my thread but I will leave you with this meat, await your cries and yelps and respond in a barely educated manner. Right now my feeling is that I am pretty happy with what I have managed to do which was install a zoned HVAC system on my own with no other manpower in under a week for a nearly 2000 sq ft area and come away with a good understanding. Feel free to beat down my euphoria but please take into consideration that purile comments that are unsubstantiated will be swiftly batted out, hopefully we can discuss this and keep the old ladies bickering to a minimum.. I look forward to your input gents (and ladies) and I promise to give you my veg which is going to be harsh words which hopefully many HVAC pro's will agree with in the near future.

Wayne

ps I do have a bunch of photos for this piece of the project and I will give you the link once I have changed the url's to move it to a more permanent area.

So here is the equipment:

Goodman GSC130421 3.5 ton 13 seer AC conditioning unit
Goodman AEPF426016 Goodman 3.5 - 5 ton variable speed air handler
HKR15C 15Kw Heat Kit (51'000BTU)
Aprilaire by-pass humidifier

The dampers are all Honeywell and are as follows:

SPRD14 14" Pressure regulated damper (Bypass/Dump) which is connected above the plenum and connects the supply to the return.
ZD10x8 dampers - I have two of these for zone1
ZD12x8 damper for zone2
ZD16x8 damper for zone 3

The thermostats are all proliphix NT150h which are network capable with built in humidity, heat, cooling capability for systems with 2 stage heat/cool. I have three of these - one for each zone.

Now the tricky part has been integrating all of this together and that is where the Honeywell control panel comes into play.

It is a HZ322K TrueZone 3Z 2HT/2CL control panel. Each of the thermostats are wired into this, each of the zone dampers are also wired into this into their respective zones for damper control and the final connections are for the air handler.
there is also a device that I bought with the control panel and it is called a discharge air sensor. This is also wired into the control panel, it is physically installed inside the duct that connects the supply and return air but it is crucial that it be placed in an area where it can sense ambient temperature which must not be above the heat packs nor after the pressure damper. What this does is sense the air temperature in the connecting duct and determined by the variable I configure on the control panel will shut down the heat or cool if it detects that the temperature in here is higher or lower than that required.

Right now my feeling is that I am pretty happy with what I have managed to do which was install a zoned HVAC system on my own with no other manpower in under a week for a nearly 2000 sq ft area and come away with a good understanding. Wayne

ps I do have a bunch of photos for this piece of the project and I will give you the link once I have changed the url's to move it to a more permanent area.

Wayne, excellent posting! thank you! I would like to see some graphics on this system to get a better understanding. I have a desire to do this DIY ac system as well, but i only need 1000 sq ft , maybe half this size, maybe 2 zones, maybe one. My problem remains ductwork in an old house.
thank you
Craig

Thanks Craig, now as for your zones I guess the question you really need to ask is 'are the zones really necessary'? It does complicate the design and to a degree the install and will certainly add to the cost. For me it was easy to decide because I quite literally had three very separate defined areas (A music studio, a rest area/tack room and a large apartment).

So why the zones for you? Is it because you have a basement that you only want to heat/cool as required? Send me an email with your phone number and we can chat - but you will want to employ the services of a competent HVAC person for 2 things #1 the design and #2 to connect the soft copper and fill...

Stupid Me not carefully reading the post.

So I have 3 zones controlled by 4 dampers (2 for the main upstairs zone and one for two seperate zones downstairs). I also have a static pressure damper to let air flow between the return duct and the supply plenum before the dampers that control the zones. I have a humidifier installed in the plenum and I have three proliphix NT150h thermostats to control it all. At some point I will put another post in here detailing all of the main parts and how I connected all the controls, dampers, electrical together. Right now I am feeling bewildered but I have faith in ductworks helping me through it and I have a real HVAC butt crack guy stood by ready to come and connect up the copper between the unit outside and the AHU, charge, check my handywork and do any fine tuning.

So right now I am a happy bunny. If anybody has done any multi zone work and using the proliphix controllers to control it all with the humidity system I sure would appreciate your input. My thought at the moment is that I somehow connect the thermostats to the dampers to open them and also connect all three thermostats to the ahu to turn on heat or cool and the humidifier? Of course this is my first stab and nothing will be connected until I have full understanding.

Thanks

Wayne

I'll have to do some homework on stats and look at your zone panel and dampers.

Remember your bypass damper and duct should be sized (I think) to bypass about 75% of CFM when only the smallest zone is calling. Airman....where are you?

Also invest in a Suction line tstat. Honeywell part FPC. It clips onto the suction line at the evap coil. Wire into the "Y" circuit to stop the compressor @ 36 degrees suction temp and restart at 46 degrees.

Trust me, I've done a couple jobs with Honeywell zone panels set everything up discharge sensor to stop cooling at 48 degrees discharge and ended up with a frozen coil. FPC is a must.

Also make sure dampers are powered open and spring close. Power the damper when heat/cool is needed not all the time it is not. Power open and power close will use power 24/7 and have an even higher fail rate.

Basically what you are doing is wiring the stats to the zone control board. Then the board to the AH and and outdoor unit. Again I haven't looked at the zone board, but you may have several different options here.

I maybe able to use voting. Meaning if 2 zones want cooling and 1 wants heat, cooling is done first and then heating. May also have a "Must serve zone" feature, so if the apartment is "must serve" and wants heat but the other 2 want cooling then the apartment gets heat.

Again, I'll have to read up on what you have to be of anymore help and will return.

Don't still be beating us up. We are behind you. And only my wife ever sees my butt crack.

Pops there is no more beating up left to do on my part, I got that out of my system within the first couple of posts :-) .. at least not to any Butt crack guys :-) My beating up is more in the manufacturing of components itself..

Why are we paying all this money hand over fist to get the most energy efficient systems yet the components that piece it all together are quite simply crap? What I mean by this for example is all of the tin stuff like boots, takeoffs and the like.

Having a decent amount of experience in the technical field especially in server room applications I have managed many projects that involve fire suppression systems that use a gas instead of water (pouring water over a running computer is not a good idea) and so the first thing we do to calculate the 'tightness' of a server room is run a pressure test to see how much air leaks out of that room. When we get into the hvac systems we do 2 tests, one with the systems on and one where we seal the supply and return vents and turn the hvac off. HVAC systems attribute to a lot of lost pressure in the room and I always wondered why.

Well now I know - even as anal as I am and sealing every hole I could catch I am quite appalled at the build quality of these components. They are put together very cheaply and even the most expensive components are much the same, simply pieces of tin folded together and the seams are not sealed. I would say that on average each component is likely to give up at least 1 cubic inch of air. Add all of these up and you just put a nice big hole in your wallet where you are constantly losing energy through the duct pieces. Gladly I went with the fiber duct so I have reduced that significantly and further more by using aluminum foil on every tin joint including the ones that have a crimp type adjustable bend and wherever possible I sealed holes with either fireblock foam or caulk. My complaint is that I am harry homeowner and obviously I have a vested interest in doing everything to the highest standard so I notice these things and fix them, we should not have to fix these problems.. they should not even exist. I am not a green tree hugger by any means but I just don't like to see money leaving my wallet because of a simple design flaw that could be fixed if manufacturers took pride in what they make. Fiber duct and insulated flexible duct eradicate a lot of this but has anybody ever thought of plastic molded components to build systems that are tighter?

I am going to speak with my ductworks guy about the things you mention here pops and by the end of this project and with your help I am sure I will have a system that does not freeze or cost me an arm and a leg to run.

I did think about what you said about the dampers before you mentioned it and it seemed silly to me to have dampers that were power closed and spring open which is exactly what these honeywell dampers are that I have purchased. What I was finding was that when the system was sitting idle; the dampers would be open and when a zone called for air/heat or cool it would start up the fan and any other device sending that conditioned air to all zones. All the manuals said I should wire them into the control panel in that configuration but I went against the grain wiring them into the panel so that power was being sent to them 24/7 to keep them closed and when a zone called for something it would initiate the circuit and 'remove' power from the damper that was making the call thereby opening the damper for that zone and leaving the others closed. This is one to take up with ductworks and thanks for 'proof checking' the design are confirming my thoughts.

As always thank you all very much for your valuable input

Last zone job used ARD dampers. Field convertable either spring close or spring open. I used spring close power open as I said earlier.

Ductwork is cheap, simply put. It's all about the install. I remember jobs (Navy base) where the Test and Balance guys could not get design air flow from equipment. You are correct, screw holes add up and leak massive amounts of air.

So, when installing ductwork have foil tape and mastic. Every joint and every seam. Join, tape, mastic!

http://www.hardcast.com/PRODUCTS/pdfs/vg181_tds.pdf

This is a DIY forum - we don't care about government rules because they suck, we care about doing the job ourselves, on a budget and doing it right which is why we ask all these annoying questions.

I haven't followed every post in this thread but it sure has been interesting. Did you do a full Manual J? In many places that is required to get a permit for the work. Or did you bother with a permit? Just wondering, since you think the rules suck so much.

I did do a manual J which was also performed by the guy that designed the system for me - so in essence 2 were performed.. somewhere in my post I think I mention me being anally retentive and doing the HVAC load calcs :D and yes I am afraid that the government rules do suck in general but the permit process is a must and actually in my recent experience it is very helpful because the inspectors (certainly here in my area) are very friendly and offer advice by the boat load and guide you through the system. So my 'government rules suck' comment may well have been geared to frustration at my own homelands ways - because seriously they do suck!