Natural gas to Propane burner

[danelectro]

Hi all,

Just thought I'd ask here.

Does anyone know what you need to do to convert a gas warm air heating system to run on Propane. Are there jets that have to be changed or what??

Any help would be much appreciated

 

[R Kraft]

Usually you would call a dealer to convert it.
Sometimes conversion kits were available.
There are tables based on the BTUs input, that tell you the size of gas orifice that you need,though I don't know what gas pressure is used in the UK.
Propane uses a smaller orifice than the natural gas required.
Sometime they used to plug the old jet and re drill it to the proper size.
But it is sort of a precision drilling operation,wallowing the hole out too big could be catastrophic.
That is how they did it here in the states ,last I knew.
Robert

 

[danelectro]

Hi Robert, thanks for the info, that's very helpful.
I had a feeling it was only the size of the jet that was an issue, I feel quite sure I could get a new jet of the correct size.
My main concern was if there was any other issue that may crop up. but i can't see one.

 

[Omniata]

Sometimes you don't need to bother changing anything...

Check to see if it has a rating plate or such like on it detailing gases and pressure...

 

[brightspark]

take the details of boiler look up heating replacement parts on google or the parts center wolsley .if its not to old jets will be available

 

[danelectro]

Thanks for the info guys.

I have taken two photos, one is of the appliance rating label, and the other is off of the electric gas valve.

If anyone knows what needs to be done, I'd be a happy man and probably buy you a beer!!!

 

[brightspark]

its a johnson starley warm air unit tel 01604 707012 spares dept they have technical advice as well

 

[danelectro]

Cheers BS,

I stuck some electric on it today just to see if it works (obviously on the summer setting only!) and everything seems to be ok, good flow of air! If I can get it to heat, my garage is gonna be very toasty in the winter

 

[brightspark]

Cheers BS,

I stuck some electric on it today just to see if it works (obviously on the summer setting only!) and everything seems to be ok, good flow of air! If I can get it to heat, my garage is gonna be very toasty in the winter

i had one in my garage there brill

 

[danelectro]

Lived in a house in the 70's with an old Johnson and starley, as a kid I used to love sitting by the vents in the winter!!!!!!

I do know of a couple of people who have recently put new models in their houses and swear by them, especially with the modern filtration, makes for a nice environment!!!

 

[danelectro]

Few more pics of my new toy!!

a couple more pics if anyone wants to see!!!

Not bad for £50 fleabay, 2001 model i believe

 

[clueless77]

contact the manufacturer for the conversion kit of parts, there will also be a new rating sticker to put over the one in your photo as this heater is set up for natural gas at 20mb, if you're running off propane it will be much higher at about 37mb. using the wrong gas will affect combustion without correct modification, high co and such like. if a gas man calls to your property and sees an appliance running on the wrong fuel he is obliged to cap it off by law as it is classified as immediately dangerous. but only if he sees it. but apart from that it sounds like a good idea to heat your workshop and something i might consider myself once i've insulated the place.

 

[danelectro]

Don't worry, it won't be installed by me, I just want to know as much as I can before someone comes round shaking their head and saying "you can't do that mate"!!! So it'll be a gas safe guy doing it. I shall give J&S a ring tomorrow see what they say.

But yeah, I'm quite pleased with my purchase!!

 

[R Kraft]

Nice looking little furnace.
Should be no problem to convert over.
Robert

 

[danelectro]

Ok today is the day I find out if this baby will run on Propane!! Wish me luck guys!!!

 

[danelectro]

Well it looks like i've drawn a blank.

Phoned the manufacturers today, and all they told me was there was no conversion kit, not even jets to buy or anything. I was trying to get the guy to tell me the difference between a propane model they DO SELL and the one I have, all he could say was that model hasn't been tested to run on Propane.

So I'm stumped right now.

 

[Justme]

What about an adjustable propane regulator?

You could then adjust the standard propane 37mb down to mains gas 20mb. Just an idea, check with an expert before doing it.

Just adding new jets is not all that would be needed. Quite often you need to adjust the air flow gap to keep the flame picture right and also in contact with the burner.

 

[danelectro]

Thanks Justme,

Got to be honest, getting anyone to assist with this is like banging your head against a brick wall.

The gas valve APPARENTLY is adjustable (i.e.pressure) and I know it needs a smaller jet. Not sure about airflow gap, could you enlighten me???!!!

I'm actually thinking of scrapping the gas side of it and sticking a kerosene ch burner in it instead, it's doing my head in!!!

AND It's only to warm my garage up!!!

 

[Justme]

Not sure about airflow gap, could you enlighten me???!!!

It was mentioned in the install manual for our new cooker. It comes in mains & LPG versions but can be converted back & forth as well. As mine came set up for LPG I dint have to do it.

If you lower the pressure you should not need to change the jets.

 

[danelectro]

Yeah We've got a LPG Cooker, all the guy did was changed the jets, the end.

I have been looking at the Gas valve, and it appears it'll only handle up to 30mbar of gas, so one could assume that (as you mentioned) you could stick a regulator on the bottle and adjust it down to 30mbar or whatever it needs. There is still the issue of the jet, would it need changing if the gas was regulated???

I've been on this all day today, and I'm beginning to wish I hadn't bought the bloody thing!!!!!

Just found this interesting little bit on the internet:
If you have ever shopped for a gas grill, gas fireplace logs, a gas stove, a gas dryer, etc., you know that you are always asked to specify whether you plan to use it with natural gas or LPG (liquefied petroleum gas). The reason you have to get it right is because LPG and natural gas have different properties.
Natural gas is just that -- natural. If you sink a well in the right spot, natural gas flows out of the ground. It is mostly methane, or CH4. Liquefied petroleum gas, on the other hand, is a product of crude oil distillation (see this Question of the Day for details). It contains mostly propane, or C3H8. Propane has the nice property that, when you compress it, it condenses into a liquid. This means that it is much easier to store in a tank than natural gas, which does not easily compress.
You can see the difference between natural gas and LPG most easily when you buy a gas stove. Normally, you are supplied with two sets of jets, one set for natural gas and one set for LPG. You install one jet in each burner. The jet is simply a little screw-in cap with a hole drilled into it. The difference is that the hole in the jet for natural gas is bigger -- about twice as big -- as the hole in the jet for LPG.

The reason for this difference is because LPG contains much more energy than natural gas. A cubic foot of natural gas contains something like 1,000 BTU (British thermal units) of energy. A cubic foot of propane contains perhaps 2,500 BTU. You can see that if you take a gas appliance set up for natural gas and then run it on LPG, the appliance is going to run more than twice as hot. In the case of a water heater, it is apparently hot enough to start a fire.