Heat Pumps and Electric Heating - Carrier coil doesn't qualify for the latest rebate?

(continued from here: DoItYourself.com Community Forums (http://forum.doityourself.com/newreply.php?do=newreply&noquote=1&p=1622714) ):

...our 'next' issue involves the aformentioned Carrier 3 ton heat pump and our inability to source a coil for same that meets the criteria for these latest government rebates. We are evidently being pushed up and in to a 4 ton Aspen coil for this unit (made by an aftermarket manufacturer) because (I'm told) somebody evidently passed on certifying their own coils for this program.

Questions:

What are the upsides/downsides of this move and what are the affects on both the heat load calculation already performed or ductwork also reworked (upsized)...

...and again, will we need to purchase a different line set (7/8" presently) for the 50 foot run to make this system work optimally when considering the added capacity of the coil?

I don't see this (from a layman's point of view) as being a big deal; yet this system was already leaning towards the oversized to begin with (small walkout log cabin with lots of windows/infiltration via flat log-to-log construction) and I would like to adjust to this latest wrinkle accordingly, if needed.

Thanks for your help! :)

As an aside, I found posts 6, 7 and 8 interesting here (from hvac-talk.com) Aspen vs. Allstyle horizontal coil - HVAC-Talk: Heating, Air & Refrigeration Discussion (http://hvac-talk.com/vbb/showthread.php?t=369262) and will contact Aspen on Monday to double check whether we qualify with their coil installed.

...also, what are the ramifications of a 3 ton compressor working with (or against) a 4 ton coil?

...and how does all of this play in if our system is possibly 'oversized' to begin with; although "properly" heat/cool load calculated ? (flat log to flat log build design...no tongue and groove...with many windows, sliders and skylights for such a small log cabin).

Aren't coils usually sized but a half ton more than the heat pump?

Thanks in advance! :)

Did anybody do a load calc?

Are you installing this system yourself?

Does the furnace qualify for the tax credit?

Thanks for the response and questions...

The load calc came in at 3 ton despite the size of the cabin (lots of infiltration); we are doing this ourselves and the furnace qualifies...yet the heat pump evidently does not without this 33% oversized (4 ton) aftermarket coil.

In doing my homework on all these different HVAC companies; it seems that many of them are having trouble meeting the requirements of 15 SEER; 12.5 EER and 8.5 HSPF for this current tax credit...and some of their coils (as sold presently) are seemingly a major cause in this.

The tax credit is 30% of installed $ with a $1500.00 max, if the furnace qualifies you should be fine. I would not use a 4 ton coil, also what are you going to use as a fossil fuel kit?

You may also want to check and see if you can get the tax credit if the system is not installed by a qualified contractor.

You would be better served taking care of the air infiltration, windows, insulation, etc. These items also qualify for the tax credit

Thanks for the advice.

We have natural gas and flat vs flat logs (tiny piece of weatherstrip in between; no tongue and groove; wood that does what wood does; caulk on the exterior)...so while replacing 20 year old windows is always good...we've come to appreciate rather than curse the 14 window/4 slider design that we're stuck with (nice air exchange!:rolleyes:) until we absolutely have to replace them.

What I can't understand is why I have to purchase a 4 ton coil to meet the government's 'efficiency' standards...when very few manufacturers seem able to hit the requirement listed above with not only commonly package units already on the shelf but properly sized to begin with! (see post #10 here: Omgili WebToolbar - Humidity control vs tax credit? - HVAC-Talk: Heating, Air & Refrigeration Discussion (http://omgili.com/jmp/uBQNNiLKiWbSvRpOnLegpZ2Srag.YNWUH4m5A7Q41TnRuvjDSCGkn8GZ8XwwVzVFrGGqjxA85.ZaQN1rRfVFYyS3H6PGDWXjfe8InEWljubIdW6it3_ppyLua7nxVayoI4NQqT4b7Y2PU4eDpI0KXDEkx06feaN1sLP6jwjvojG3iKkjWGh.qyGJ1sQPJypMs3LyblwE7q.VjBMennvXvSsGTlje0yYfyqAe9tKLp6CDWxms1ns79w--) ).

Again, my question is...what potential problems (efficiency related or not) am I looking at with a 3 ton heat pump married to a 4 ton coil up here in Michigan?

Thread closed...Thanks...(I will continue to help others on this forum when I can). :coffee:

You may have closed this but you did not answer your own answer before closing. First Carrier/Bryant do not make Air Handlers or evaporator coils with a certain sizes like 2,3,4,5 Ton for their high efficiency systems.

They use a variable speed blower motor. Air Handlers are now labled with a 02,03,05,06 Their High efficient Furnaces also use a simular concept

These motors they use in these systems are EMC motors that controls everything now. http://www.thedealertoolbox.com/products-indoor.php (Think Tank 3.0)

Carrier and Bryant use software written controls in their high end systems Infinity/Evolution Series to control the blower motor to work with components so they perform at efficiencies stated for the tonnage size requested.

We are in a new world of air conditioning and heating, it's not just slap in a 3 ton air handler with a 4 ton coil with a $50 dollar blower motor. These motors are Expensive and are controlled by a communicating software written Controller which is the brain child of the system as a whole.
Next there is after market evaporator coils you can use. But you should first look at a system match from Carrier or Bryant.( Furnace, Evap Coil, Condenser). I can find several 3 ton hybrid heat systems that match up so there should be no need for an after market coil. Plus the Carrier/Bryant coils are warrantied for 10 years.

Update:

As my unanswered questions indicate; we were forced to go with a (std.) 1/2 ton upsize on the coil and forgo the tax credit.

Warning to others out there installing systems at this time:

Either check your ethics at the door and allow your contractor to sell you a $5000 95% efficient furnace (30% of which equals the $1500 credit)...

...or question them to the point of no response given (see above) as to any supposed efficiencies 'gained' :mad: when oversized coils are installed to correctly meet ALL of the criteria presently required.

Responses went strangely quiet on another professional HVAC forum when I asked the same questions (then quickly changed to attacks)...so if the 'professionals' pushing these systems won't even admit that it's happening...one can be certain that one will run into either the former or the latter until engineering catches up with what is required (all models/manufacturers do not apply here...but the above shut up enough "cheating and fooling" installers to prove the point).

Buyer Beware! :alarm:

...by the way, we were .1 away from qualifying with the 3 1/2 ton coil...

"..I can find several 3 ton hybrid heat systems that match up so there should be no need for an after market coil. Plus the Carrier/Bryant coils are warrantied for 10 years..."

Lots of systems 'match up'...yet they still have to meet or exceed the numbers in each of the three categories that the government requires to qualify for the tax credit.

Your earlier post (rightly) educates us all on the wonders of 21st century equipment...yet does not explain why manufacturers are presently rushing to market 'new' models with nothing but incremental changes solely to hit government mandated tax credit thresholds (presently) unattainable in certain system configurations.

Again, you can either put in a bigger (lesss efficient) coil to hit these numbers on SOME models or fudge the furnace price...neither of which was acceptable to us.

Thank you for your input. :)

It is buyer beware out there with these Tax Credits. Desperate times for some of these suppliers, they are going to get stuck with inventory that they cannot get rid of easily. Hmm might be a deal or two out there for a savvy buyer. Todays buyers are able to get all needed info from a easy internet search most actually know a lot more about there final choice of unit than the dealer/installer these guys hardly ever bother to read the manufacturers information they just want to read the bottom line profit statement at the end of the month.

As my unanswered questions indicate; we were forced to go with a (std.) 1/2 ton upsize on the coil and forgo the tax credit.



You could have gone with a higher SEER and or differant system to get the credit. You seem bent on trying to make what you bought work, not a good idea. As stated its the V/S motor on the furnace that will bring up the specs.

The tax credits are very straight forward, all you need to do is get an ARI matched system, not hard to do. I install them every week. As long as its installed by a qualified contractor in your primary residence its no problem.

Oh yeah, I do this without increasing coil size or using after market coils. I install Amana, Bryant, and Trane. I have no idea what you mean by fudging the furnace price, the tax credit is off the entire installed price not the equipment.

I read your other thread in the other forum as well, quite frankly I don't think you have a clue as to what your doing and are trying to blame the entire HVAC industry and the government because you can't get your unqualified system qualified.

Lots of systems 'match up'...yet they still have to meet or exceed the numbers in each of the three categories that the government requires to qualify for the tax credit.

Your earlier post (rightly) educates us all on the wonders of 21st century equipment...yet does not explain why manufacturers are presently rushing to market 'new' models with nothing but incremental changes solely to hit government mandated tax credit thresholds (presently) unattainable in certain system configurations.

Again, you can either put in a bigger (lesss efficient) coil to hit these numbers on SOME models or fudge the furnace price...neither of which was acceptable to us.

Thank you for your input. :)


how can you put in a bigger less efficient coil and get a higher efficiency rating? :wall:
You are talking parts, I'm talking systems. This isn't Frankenstein A/C it's more like the Jetsons.

A larger coil has more surface area to get a more efficient rating. Larger coils just don't stop with your evaporator. Take a look at the outside units. The condensing coils are larger too!!

Check for your self on how many variations qualify for the tax credit with your carrier hybrid heat you are thinking about.
2009 Carrier Ratings (http://66.98.196.147/carrier-tax/hp_certified_list.php)

Next,
why are you so hell bent on the tax credit or the honor of $1500? You know how much it cost for a HVAC contractor to buy a 95% furnace and then the cost of the installation process by a trained factory authorized professionals? I don't think you do, We don't work for beer you know, that's the Frankenstein A/C company.
it takes licenses, training, workmans comp. liability insurance, vehicle, gas, shop, customer service funds and a 1000 other things that legit contractors have to have in order to install a furnace!

It can cost every bit of $5000. And when this health care passes its going to cost you 7,000 for just the furnace!


I haven't used an aftermarket coil with a Bryant System yet. :thumbup:
check out the carrier link I gave you and then enjoy your full fledged Hybrid Heat Carrier Infinity system that qualifies for the tax credit!!

ps.
your negative energy is not healthy.