Home, Workshop, Utility, Patio, Garage and Portable Heaters - Nat Gas usage in outdoor patio LP heater

I have an outdoor LP patio heater that I would like to power with natural gas. I would rather not drill out an orifice.
Will the heater work if I remove the LP regulator and connect directly to the NG line. I assume that the BTU output will be less, which should be OK if it is not too low. It is a 40,000 BTU LP heater. Even half of that would be OK.

Hello T Nash. Welcome to Gas Appliances topic and our Do-It-Yourself Web Site.

If you can at least convert the regulator from propane to natural gas, do so. Should be a quick and easy process. Very likely turning over the towers cap on the regulator or turning a lever or set screw. Depends upon brand & model of regulator.

The burner would burn reasonably well with a converted regulator versus no regulator. Flame would be smaller then it is presently (BTU under rated) but would provide heat without much adverse effects. To some degree at least but not provide the heat nor the light, as it does now.

How the flame would be without any regulator in line needs to be determined or discovered. (Read below*) Not sure but you can try it and see. Most likely the flame would not be correct, since the unregulated gas flow would be twice as much as it should be. Through a smaller orifice size then required.

*Normal house line pressure out of the gas meter is between 7 to 10 inches of water column. Which is about 1/4 to 1/3 pounds of pressure. About twice what is needed for a natural gas appliance.

*Appliances regulators are set for 3.5 inches or 4.5 inches of water column. About and near half the in-line out of the meters house pressure.

Without a regulator and a propane orifice instead of a natural gas orifice can be tried and may be okay. However, replacing the existing 40,000 propane orifice with natural gas 40,000 BTU orifice is the best operational and service method.

Should not be all that difficult to access the existing orifice and replace it. Replacement orifices available at any local appliance parts store in your area.

Use the reply button to add additional information or questions. Using the reply button keeps or moves the topic back up to the top of the list automatically and keeps all communications on this subject in this thread.

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Hi Sharp Advice,
Thanks for your input. I will give it a shot without a regulator .

Additional questions:

What is the normal output of the LP regulator in this situation? i.e Would NG at house pressure work with the LP regulator?

Thanks again,
tnash

I bought the 40,000 BTU stainless steel patio heater at Home Depot and would like to know what steps are necessary to convert it so it can be supplied by natural gas. The box says it is a GardenSun model 648-366, however the instruction manual says it is model HSS-A-SS.

I consider myself pretty handy and I have all the necessary tools to do the job, just need step by step instructions.

Regulator?
drill out orafice?

Thanks.

To give you a little more information:

I took off the large screen from the burner unit and took some photos:
http://pyskadlo.homestead.com/files/ph1.jpg

Here, you can see that the orifice has a mesh screen on the inside:
http://pyskadlo.homestead.com/files/ph2.jpg

Should I drill out the mesh? Looking forward to receiving some help with this project.

Hello skaggs. Welcome to the Gas Appliances topic & the Do-It-Yourself Web Site.

First off, you do not drill out the screens anywhere. All that should be required is to convert the regulator or replace it with an "NAT" regulator.

Then drill out the orifice to drill bit size 32. Or simply replace the orifice with an "NAT" gas orifice. The drill bit size is per the gas utility specific gravity conversion chart for gas pressure of appliance regulator at 3.inches water column pressure, should you elect to drill or out.

Be aware, the orifice size must be exactly the correct size. One size larger and the burner will be slightly over gassed. Over gassed means a flame to large. Which will create odors and soot. One size to small will decrease the flames size and simply produce slightly less heat.

Next item is the regulator. May not or likely not be a convertible regulator. If non convertible, must be replaced. If convertible must be done. Move lever, turn set screw, etc. which ever is available.

Nothing more should need to be done, with the exception maybe the fuel supply hose replaced to allow it to be connected to a gas supply several feet away.

Patio and fireplace chain or privately owned retail shops will have parts needed. Visit one near you.

Use the reply button to add additional information or questions. Using the reply button keeps or moves the topic back up to the top of the list automatically and keeps all communications on this subject in this thread.

Web Site Host, Forums Manager, Moderator Hiring and Promotions Agent, Gas Appliances Topic Moderator, Multiple Forums Moderator & Natural Gas Appliance Diagnostics Technician.

Thanks for the reply.

I'm sorry if this is an obvious question, but where is the orifice? What do I have to take apart to get to it? I plan to remove it and go to a local store named "Best Fire" to get one that is "NAT".

Could you elaborate a little on how to determine if the supplied regulator is convertible or not?

Thanks again.

Hello: skaggs

Oops! Correction made in my post. "LP" changed to "NAT"
I got confused...:eek: since you made your post a reply to another members post and not a new post as a new member.

The orifice is at the base of the burner. (Where the inlet hose is attached in the photo provided) The burner must be removed and/or separated from the gas supply line. Burner may screwed on and/or secured somehow.

Orifice will be a brass or bronze hex head nut with a tiny hole directly in the center of it. Center of orifice may be or should be slightly concaved.

YES. I would highly suggest you buy the correct orifice before removing the existing one. It this manner you'll know what you're looking for having the new one already and how it will be installed and the existing one is to be removed.

On the regulator, "LOOK" for some way to moved something and the words "LP" and "NAT." If the words are seen the regulator is convertible. May have to move a lever, turn a set screw or flip over a cap, etc.

If no means or method is found or can be determined, ask how, at the store you go to where the orifice can be purchased. They would know, advise you. It's in their best interests to do so. Since they sell those parts and want to sell you the part.

BTW: (By The Way)
Excellent photos and glad you posted them too. Helps plenty...:thumbup:

I took apart the base of the burner in an attempt to find the orifice. Is the orifice the gold piece tack welded to the metal angle? How would I get this off and reattached? It seems it may be easier to drill it out? I don't have any welding equipment. Here's a few photos:

http://albanyhdtv.homestead.com/files/orifice1.jpg

http://albanyhdtv.homestead.com/files/orifice2.jpg

http://albanyhdtv.homestead.com/files/orifice3.jpg

Also, it doesn't look like the regulator is convertible, does it?

http://albanyhdtv.homestead.com/files/regulator1.jpg

http://albanyhdtv.homestead.com/files/regulator2.jpg

http://albanyhdtv.homestead.com/files/regulator3.jpg

What about the hole in the attachment at the end of the hose?

http://albanyhdtv.homestead.com/files/hose1.jpg

I don't want to get into a welding issue. What's my best option?

Hello? Sharp Advice? Where are you?

:coffee:

Hello: skaggs

Where am I? I'm here, almost everyday and there too and just about everywhere else on this site almost everyday. Except for boating, fishing and or target shooting days...:)...:D

Try to tend to my forum topic and reply to as many posts as is possible within some time limits but there are times I unintentionally skip or miss a post here or there....:o Kindly excuse this late reply....:)

Picture one is as close to the right one as is possible. All other photos are not those which are likely to contain the burner orifice. Last photo, at the bottom in the post, is the gas supply hose with the connection nut attached.

The orifice, if there even is one, is either in the top section of the adapter in photo one, two or three from the top or at the top of the aluminum tube extending from it. Which would be up under the shroud at the base of the burner head.

The regulator, photos 4, 5 & 6, indicate the regulator isn't convertible. Would have to be replaced. The hole in the regulator controls the gas pressure out of the propane bottle, which is slightly higher then the burner needs or the pilot needs.

Thus, two orifices. (Thiner aluminum tube for the pilot gas to it's orifice and larger aluminum tube for the burner) One for the burner and one for the pilot. Both would need to be replaced to totally covert the appliance.

Both located up under the shroud covering burner head.

Best suggestion, take the entire part to a local appliance parts store and or outdoor appliance patio/BBQ store and obtain the conversion parts, if any are available for that brand & model.

May or may not be convertible appliance...:confused: Inquire at the store but do not be surprise if it isn't convertible either.

I took the shroud off and took some more pictures. I placed some arrows on the photos where I think the orifice(s) may be.

Do I have any of the orifices labeled correctly?

PHOTO #1:
http://albanyhdtv.homestead.com/files/orificehelp1.jpg


PHOTO #2:
http://albanyhdtv.homestead.com/files/orificehelp2.jpg


PHOTO #3:
http://albanyhdtv.homestead.com/files/orificehelp3.jpg

Hello: skaggs

Photo # 1 shows the burner orifice.

Photo # 2 shows same orifice (as in number one) indication arrow marked # 1

Photo # 2 indication arrow marked # 2 is thermocouple connection location.

Photo # 2 indication arrow marked # 3 is pilot gas tube.

Photo # 3 indication arrow marked # 2 is thermocouple adapter hex nut and also where T-Couple connects into ASO (Automatic Shut Off) device.

Photo # 3 indication arrow marked # 3 is the hex nut on the T-Couple. (Thermocouple)

To an answer your question: YES. #1 is the orifice.

BTW# 1:
For the benefit of all readers of this thread, a thermocouple is not called a thermocoupler...:thumbdn:

It's called a thermocouple...:thumbup:....:)

Often abbreviated as T-Couple....:D

Now what where you intending to do?...:o...:confused: I 4got...:o...:wall: So busy with so many other things on this site and in personal life, etc, I forgot (4got).........:o

BTW# 2:
Once again EXCELLENT PHOTOS!!!!
I ought to hire you to do my photos....:)....LOL!

I am planning on using this with natural gas. It was sold as a LP gas patio heater.

Thanks to you advice, this is what I believe I have to do in order to get this to work with Natural Gas:

1. Either go to a patio/fireplace chain store and get a NG orifice to replace the existing orifice or drill out the existing orifice with a size 32 drill bit.

2. Replace the regulator with a NG regulator.

3. Get the appropriate supply hose and connectors to hook up to the NG supply.

Is this correct?

Also, a few questions...

What is a size 32 drill bit? Is it a 1/32" drill bit?

Is the NG regulator necessary? I have a NG grill and there is no regulator (that I see or use). It only has a ball valve to turn the NG flow on/off.

Is there a limit to the length of supply hose? Would 20' be too long?

Thanks for all your helpful responses.

Numbers 1 (one) through 3 (three) are all correct in your above reply post.

# 32 drill bit is not the same as a 1/32 drill bit....:thumbdn: Get the correct size before drilling. And be positive the new drilled hole is EXACTLY centered into the existing hole.

Also be sure to remove any burrs. Burrs can and will cause the gas to angle out of the orifice instead of going out straight up.

Be ADVISED.

#1
Small bits break very easily!

#2
DO NOT overly squeeze or tighten any orifice into a vise to secure it. Doing so will cause it to become out of round in circumferance.....:eek:........:thumbdn:

#3
Gas heater MUST not be over-gassed either by over sized orifice sizing or lack of a regulator. Either one or both above will cause soots & odors. Worse yet, Carbon Monoxides to those in the area of the heater.

Gas supply hose size? Buy any which meets the codes in your area. Codes my vary.

You're welcomed. Hope this is all. Good Luck.

I removed the orifice and took a few photos. It was a 1/4" hex nut that I used to unscrew it.

http://albanyhdtv.homestead.com/files/orificealone1.JPG

http://albanyhdtv.homestead.com/files/orificealone2.JPG


Now, off to the patio/fireplace store!

I am working the same conversion of the HomeDepot patio heater. The regulator is fixed and sealed at 2.8kpa which is about 11", so I'm thinking that a direct connection for NG is right. The orifice is a No. 47 (0.078), so for equal pressure, is that still correct that it should be opened to No. 32 (0.116)?

The valve P/N is AH902D01 <http://www.alibaba.com/product-free/10446610/Patio_Heater_Gas_Valve.html>

I am working the same conversion of the HomeDepot patio heater. The regulator is fixed and sealed at 2.8kpa which is about 11", so I'm thinking that a direct connection for NG is right. The orifice is a No. 47 (0.078), so for equal pressure, is that still correct that it should be opened to No. 32 (0.116)?

The valve P/N is AH902D01 <http://www.alibaba.com/product-free/10446610/Patio_Heater_Gas_Valve.html>

I'm having difficulty finding an orifice at the local appliance/patio/grill stores. It may be easier to just drill out the orifice.

Sharp Advice...as Measure Twice asked, will a #32 be correct for the setup he describes? Since a #32 = .116, this is just a little less than half the size of the 1/4" hex nut.

I have been working on tooling to make this part. The thread looks like M6x0.75. Here's what I've found for the stock and tool:
http://www.sdp-si.com/d790/PDF/D790C04022.pdf
http://www1.mscdirect.com/CGI/N2DRVSH?PACACHE=000000078741039
There's the question, as you noted, of the line between the valve and orifice being small (hence the small thread) so that the No. 32 will almost be the same as the orifice backside diameter. I'm not an expert on fluid dynamics, but the depth of the orifice has an influence on the mass flow. I am going to research this before I settle in on a drill size. It would seem to me that if going from 47 to 32 is ok for the same pressures of the two gases through the same depth orifice, then just drilling this through would effectively increase the depth to the entire brass part. An educated guess would put the diameter in this part at no more than 0.100. If you try opening up your's, let me know what your flame is like.

Just another thought. If you don't have a lathe or even a drill press, put the drill bit into a vise and put the brass part in the drill. This will help to keep the hole in the center (minimum angular velocity effect, boring).

Where can I buy a numbered drill set at a brick & mortar store? Home Depot doesn't carry them.

I hope Sharp Advice answers our questions soon.

You will likely have to go through an HVAC or plumbing supply house to get the orifice drill you're looking for. No big box or hardware store will carry them.

I went to a local gas burner appliance shop today and they drilled out the orifice for me.:)

I came home, put the heater back together and went outside to fire it up. Unfortunately, it seems as if the pilot cannot supply enough NG to keep a pilot light lit. :( The NG would ignite in the pilot tube for a few seconds after I pressed the ignitor (while keeping the dial pressed in as per instruction manual), blue flame would shoot out the pilot tube, but immediately go out after a fraction of a second. My novice opinion is that there is not enough NG being supplied to the pilot.

There must be some sort of safety feature that will not allow NG out of the burner until the pilot is lit. I was able to "fool" the safety by clicking the ignitor, getting the pilot to light (for a half second) and then immediately turn the knob to high and hit the ignightor again. A nice, blue flame came out of the burner. :D

Does anyone know a fix for the pilot? Does it sound like a supply problem to the pilot?

skaggs

Orifice for propane to small for natural gas usage. That's the only supply problem. Solution below.

Pilot orifice, Just in case you're wondering, Yes. There is a separate orifice for the pilot flame, which must be replaced or drilled out also....:thumbup:

Correct orifice size is unknown to me. Also drill bit size unknown. Best bet, once again, is to replace it and not attempt to drill it out. Since the orifice size is unknown.

The place you went to should have the orifice and or may be knows what size the pilot orifice is or should be. That info may or may not be in the service manual....:confused:...???

Might have to obtain pilot orifice Btu size from a model that is designed and intended to be used with natural gas.

Here are some photos of the main burner orifice after it was drilled out with a #29 bit. The appliance store tech came up with a #29 by measuring the existing orifice hole size with a micrometer and then finding the BTUs for that size on an LP orifice size chart. Then taking that BTU number and finding the corresponding size NG orifice on a size chart. It came out to a #29.

http://albanyhdtv.homestead.com/files/orificedrilled1.jpg

http://albanyhdtv.homestead.com/files/orificedrilled2.jpg

My conversion is complete!Beer 4U2

I accessed the pilot orifice, which was "hidden" inside a larger tube or conduit, by loosening the screw holding the pilot orifice and then pulling it out. The orifice then simply unscrewed from the small NG pilot supply line. See photos below.

http://albanyhdtv.homestead.com/files/pilotorifice1.jpg

http://albanyhdtv.homestead.com/files/pilotorifice2.jpg

I then drilled out the pilot orifice with a 1/32" drill bit, screwed it back onto the NG pilot supply line, replaced the supply line inside the larger conduit, and tightened the set screw.

I took the burner outside, hooked it up to the NG supply, and the pilot lit on the first try. With a simple turn of the knob, the burner then fired up with a beautiful blue flame. :p

Project complete! :thumbup::thumbup:

By the way, the appliance store tech said you can purchase a set of numbered drill bits from Harbor Freight. Link to numbered drill bit set (http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=34627) They have a set that includes numbers 1 thru 60 for $9.99. While it is not "professional" quality, it should do just fine for the Do It Yourselfers like us.

Not related to the project, but I wish everyone took pictures as well. Esp with the labels and all.

Here's the Orifice Capacity Chart that was given to me at the local appliance shop:

Download Orifice Capacity Chart (http://www.box.net/shared/6gmf5b4ddx)

I'm doing the same project and am grateful for your posts as well as your diligence in completing this.

My question is this:
You said you drilled out the pilot orifice with a 1/32" drill bit. I do not have, nor can I find, a 1/32" drill bit. The closest thing I can get is a 3/32" drill bit. Can I use that or can I use a
1/64" ?


thanks,
gv

I'm doing the same project and am grateful for your posts as well as your diligence in completing this.

My question is this:
You said you drilled out the pilot orifice with a 1/32" drill bit. I do not have, nor can I find, a 1/32" drill bit. The closest thing I can get is a 3/32" drill bit. Can I use that or can I use a
1/64" ?


thanks,
gv

The smaller, the better. I would guess the 1/64th bit would be just fine. In fact, the 1/32 hole produces a pilot flame that is very large, probably too large.

Theoretically, you should measure the existing pilot orifice and then use the chart I posted previously to determine the correct NG orifice.

The smaller, the better. I would guess the 1/64th bit would be just fine. In fact, the 1/32 hole produces a pilot flame that is very large, probably too large.

Theoretically, you should measure the existing pilot orifice and then use the chart I posted previously to determine the correct NG orifice.

My fault... I should not have said a 1/64" I should have said 1/16"... I know, I know... BIG difference. So the 1/32" is too big as well huh?....

As for the conversion chart... it might as well be in Latin as I do not understand it at all. Could you (or anyone) give me a primer on how to read it please?
Thanks,
gv

As for the conversion chart... it might as well be in Latin as I do not understand it at all. Could you (or anyone) give me a primer on how to read it please?
Thanks,
gv

You need a micrometer to measure the size of the existing opening. (or have your local gas burner store measure it for you)

1. Find the size in the 2nd column on the left
2. Look across the line to see the BTU for LP gas.
3. Look under the Inches of H2O: 3.5 for Natural Gas and find the closest to the BTU found in #2 above.
4. Follow this line to the left to find the correct drill size for the same BTU

Hi,
I drilled the hole as prescribed but I could not find a 1/64 drill bit so I used a #60 bit from the drill set advised above which I got. Now it is obvious that the gas flow is too strong.
Any suggestions?
Thanks,
gv

Unfortunately, you are probably SOL on fixing the oversized orifice and will have to get a new orifice from the manufacturer. When you do so specify you want an orifice for natural gas.