propane converter installed?

[jrhansen]

Hi, first time posting here. I inspected a gas forced air furnance that runs on natural gas, but noticed a sticker stating it was fitted for propane. It's a Trane XE 70, Model #TUS100B936A0, manufactured around 1990. Is there some easy way to tell if it has a propane converter kit installed when it shouldn't be? BTW, the heat exchanger was replaced in Nov. 2004.

Download Attachment: propane or natural gas.JPG

68.68 KB

Download Attachment: propane sticker.JPG

51.23 KB

[Jim Katen]

Originally posted by jrhansen

Hi, first time posting here. I inspected a gas forced air furnance that runs on natural gas, but noticed a sticker stating it was fitted for propane. It's a Trane XE 70, Model #TUS100B936A0, manufactured around 1990. Is there some easy way to tell if it has a propane converter kit installed when it shouldn't be? BTW, the heat exchanger was replaced in Nov. 2004.

As best as I recall, when you convert one of those, you replace a small spring inside the combination valve and you replace the burner nozzles. It's nearly impossible to tell whether or not the conversion has been done just by looking at the machine. You have to rely on the sticker or on the flame.

How did the flame look?

- Jim Katen, Oregon

[jrhansen]

Originally posted by Jim Katen

Originally posted by jrhansen

Hi, first time posting here. I inspected a gas forced air furnance that runs on natural gas, but noticed a sticker stating it was fitted for propane. It's a Trane XE 70, Model #TUS100B936A0, manufactured around 1990. Is there some easy way to tell if it has a propane converter kit installed when it shouldn't be? BTW, the heat exchanger was replaced in Nov. 2004.

As best as I recall, when you convert one of those, you replace a small spring inside the combination valve and you replace the burner nozzles. It's nearly impossible to tell whether or not the conversion has been done just by looking at the machine. You have to rely on the sticker or on the flame.

How did the flame look?

- Jim Katen, Oregon

That's the other thing. The flame was bluish-orange. If the converter kit is still installed, could that have accelerated the wear on the heat exchanger?

Jay Hansen

[hausdok]

Accelerated? It's an 18 year old furnace that has an average life expectancy of only about 20 years from install. It wouldn't be unusual to find one toasted at that age.

OT - OF!!!

M.

[Jim Katen]

Originally posted by jrhansen

. . . That's the other thing. The flame was bluish-orange. If the converter kit is still installed, could that have accelerated the wear on the heat exchanger?

Jay Hansen

I doubt it. The propane conversion has smaller nozzle orifices and the converted combination valve anticipates that the incoming gas is at a higher pressure. If you had a propane furnace that was being fed by natural gas the flames would anemic. They might not even ignite.

What would destroy the heat exchanger is the opposite condition. If you ran propane through a natural gas burner, the flame would be much more agressive.

- Jim Katen