furnace change to propane kit

[olars]

I have a lenexx furnace mod number G12Q3-110-3 I need to convert it to propane. The store where I live does not have the convertion kit. Can any one help me? I would be willing to buy the whole modual or whatever it get this running please hurry winter is comming way up here in North Dakota.

[RegUS_PatOff]

is this the Gas Valve used on your unit (or what brand & part number do you have) ?

GSV800A1476A Gas Valve

then they may have the conversion kit for LP

[Samurai Appliance Repair Man]

Dayyam, Reg, I was lookin' all over for a supplier. How'd you find that?

You and Pegi are both master infonauts! :ufo:

[RegUS_PatOff]

just searched Yahoo or Google  for "G12Q3-110-3"

[olars]

Hi This is the part number on the furnace not the number on the gas valve can you tell me again where to find the part?

[RegUS_PatOff]

can you get the number of the Gas Valve ?

[olars]

thank you so much for the help the Number on the valve is SX242NB Could I just bolt any old propane valve onto the tube? I have an old furnace valve but I do not know what the make of the furnace is I do know that the pipe fitting is the same. What would happen If I just bolted that old piece on? I really would rather just buy the right new piece though.

[dkpd1581]

The biggest issue related to changing over a furnace from NG to LP is the size of the orifice (also called the Spud).  These are the brass nuts just before each burner assembly/venturi. Natural gas uses a different size opening than LP; furthermore, LP also requires a different pressure setting at the gas valve.  This is necessitated by the fact that LP is heavier than NG and has a different fuel/air mixture ratio than NG and this accomplished through the higher pressure and different orifice size.

First you must get the spuds with the correct orifice sizes installed into the gas manifold pipe for each burner in the furnace.  You then must adjust the the pressure at the gas valve up from 3.0-3.5" WC to 11" WC or whatever OEM spec is reccomended.

You will most likely need a gas regulator (not the same as a gas valve which is located within the furnace compartment) from the propane tank to the gas service line to the house.  The tank company can handle that issue for you when the tank is set and filled.  The inlet pressure to the gas valve from the gas regulator needs to be be ABOVE 11" WC to ensure that there is sufficient pressure and volume to the gas valve or else it will not hold open the gas valve in your furnace properly and will give a pulsing sound as it flutters open and shut. It will sound like a pulsing jet engine.

You will need to check the operation of the machine and proper adjustment of the flame.  Proper adjustment is all blue flame with a light blue inner and darker blue outer halo - no yellow, no lazy drifting flame.  The operation of the machine is checked by matching the temperature rise across the exchanger (difference between inlet temp and outlet air).  It must fall within the prescribed limits that are listed on the name plate inside the furnace compartment.

In all you will need a few pipe wrenches, thread tape, manometer, temperature probe, adjustable wrench, soap bubbles, correct sized spuds, screw driver, and possibly hex wrench set.

If you have never done this before or had any training/experience in doing this, you might not want to go this alone.  You may end up exercising your Home Owner's Fire Insurance deductible. It really depends on you skill and experience level.

Best of luck.

1*

[olars]

Thanks for the input. I will see if the old furnase has those orifaces the same thread pitch so I can use them. I had a propane furnace in the shop but the thing died. so everything into the garage is already for propane. In the past I had only changed the orifaCE IN THE GAS VALVE IN THE FURNACE.