NG vs LP Garage Heaters: Off-topic discussion forum: Grassroots Motorsports Magazine

Subscribe get a full year for only $19.95 Sample get a free issue—no strings attached

Nov. 3, 2009 6:54 a.m. littleturquoiseb HalfDork

So as a very cool anniversary present my wife got me a pair of garage heaters. She went to Harbor Freight and got the last two they had in stock for a totally killer price ....

20,000 BTU Blue Flame Heater

The problem is she got the Natural Gas Version not the Propane Version ... We have no NG at our house ... I was planning on running our house propane to the garage.

According to the manufactures website,

Vent-free heaters cannot be changed from one gas type to another. The Canadian Standards Association has certified each individual heater according to the type of gas being used. Converting the gas type will change the certification and void any warranty on the heater.

Sounds like Lawyer speak to me ... So do I have a chance to convert these suckers or should I put them on Craigslist and take the money to buy the right ones knowing it will break the wife's heart to know she got the wrong one?
Nov. 3, 2009 9:10 a.m. Trans_Maro HalfDork

I used to service the Mr. Heater brand heaters.

The only difference I know of between LPG and NG is the regulator and orifice size.

You might want to look at a Kerosene forced air heater. Propane units create moisture, a lot of construction companies won't use them for that reason. You might find your bare metal rusting with propane.

Kerosene doesn't have the same moisture problems and I prefer the smell.

Shawn
Nov. 3, 2009 10:32 a.m. NYG95GA SuperDork

Trans_Maro wrote: The only difference I know of between LPG and NG is the regulator and orifice size.

That's how I understand it. The difference in operating pressures requires a much smaller orfice hole, and the regulator must be set to much higher pressure.

The OP's principle problem lies not with the type of fuel used, so much as his desire to maintain marital harmony. At this point, he must modify the gift uniits to operate on the available fuel source, hopefully without the wife knowing that she had gotten the wrong kind in the first place.

I doubt that a licenced dealer will want to change the units outright, due to the lawyer-speak issue, but you may be able to find a HVAC guy who moonlights on the side to do it. You could source the regulators and orfices yourself, but in my experience this often proves difficult, since most HVAC distributors will only sell to licenced guys.

Another tact might be to figure out where she got them, see if they have the NG units; tell them the story, throw yourself on their mercy, and hope for understanding and an exchange. In this case, you will want to deal with a married rep instead of a single one, as they will more likely understand your plight.

Good luck in pulling off this caper without her knowledge. Keep in mind that if you do pull it off, you can't ever tell anyone about it, and hope she doesn't read this thread!
Nov. 3, 2009 11:21 a.m. 914Driver SuperDork

"Honey, you bought a diesel, we need the gasoline model".

It's the thought that counts, having a piece of equipment you cannot use was probably not her first thought. Contact HF online and see if you can exchange them for an LP model, they would be more understanding that a high school kid behind the counter at your local HF.

I'm in the process of installing a 75,000 btu guy in my garage. I was doing it myself using a 100lb tank. The tank is $100, after X number of years, just like your Bar-B-Que 18lber, it's no good, buy another. My wife foolishly thought I could blow the garage up, (it's 140 ft. from the house which is why I don't have NG out there) so she contacted a gas supplier. They do all the hook up, install the tank, run the lines, fill the tank, light it off and make sure it's safe. When the tank is 1/2 empty, they come and fill it. Initial cost is ~$400, but what's your piece of mind worth?

I'm pretty sure your wife will understand.

Dan
Nov. 3, 2009 4:28 p.m. littleturquoiseb HalfDork

Contacted the Local HF ... It's the only two they had ... The new ones are dual fuel, and I could get my money back and upgrade to the tune of about $200... Look Identical just use either fuel.

I also use 100# tanks at our house (live in the boonies, no NG lines). I have two of them and switch the hose when the oven stops working.... Call the company and they deliver a fresh tank for about $100. Much cheaper then the company that deliver and refill your bigger permanant 250# tank.

I can run my own lines ... I removed the lines when we went to an electric dryer so all I have to do is uncap the manifold, run the line about 15 feet and drill one hole.

Its looking like it might be best to pony up the dough and get the dual fuel ... I can step up to the bigger 30,000 btu and have one unit insted of two... should save on LP too!
Nov. 3, 2009 6:34 p.m. stuart in mn SuperDork

Remember that those vent free heaters will be filling your garage with carbon monoxide...if I were you I'd keep a door cracked open and/or get a CO detector for when you use them.
Nov. 4, 2009 5:59 a.m. littleturquoiseb HalfDork

stuart in mn wrote:

Remember that those vent free heaters will be filling your garage with carbon monoxide...if I were you I'd keep a door cracked open and/or get a CO detector for when you use them.

Yea good thought ... it's an attached garage so venting will be nessessary at all times. Good thing is it's only going to be used when I'm not using the wood burning stove. The wood burner is in the room attached to the garage but it makes the house to hot to live in!
Nov. 4, 2009 9:07 a.m. Trans_Maro HalfDork

Vent-free heaters are supposed to have a low-oxygen shutoff in them by law.

They will go out before you even notice the air getting funky.

That being said, I wouldn't rely on the auto shutoff, just keep a window or door open.

Shawn
Nov. 4, 2009 9:39 a.m. Hal HalfDork

stuart in mn wrote:

Remember that those vent free heaters will be filling your garage with carbon monoxide...if I were you I'd keep a door cracked open and/or get a CO detector for when you use them.

But that is not the worst problem with them. As pointed out by Trans_Maro they have sensors that take care of that problem. Years ago my wife got one that looked like a fireplace to use in the family room that we added to the house.

It heated the room very well and there was never any gas smell nor did it set off the CO detector. The problem was MOISTURE.

At first we noticed a film on the windows just like when I used to smoke in the house which was bad enough but then I noticed that the drywall ceiling was buckling.

It got so bad after a couple years that we had to replace the ceiling. And when we did we got a new stove that uses a double wall chimney that draws its air from outside and vents outside also.
Nov. 4, 2009 9:40 a.m. Wally UberDork

Or at least keep a canary around.
Nov. 4, 2009 11:34 a.m. littleturquoiseb HalfDork

No Canarys ... I hate birds as pets ... It's not going to be run too often and it will only be used to "take the chill out" of the garage... get some heat into the slab. It isn't insulated on two sides, but has living space above, so venting is paramount.

I am concerned about the moisture, I live in NJ sorta on a lake ... so moisture is part of our everyday life, we run 70-90 % humidity all summer long, everything is wet 24-7!