Raypac 2100 Ignition Problem

[charlied]

My heater has an electronic ignition (called "IID"?) and has stopped lighting the heater.

The igniter is sparking just fine; you can clearly hear it, and I pulled it and visually confirmed the arcing.

The heater HAS lit once or twice this season, but does not light regularly. I pulled the ignition module out and blew through the tube that takes gas from the thermostat to the pilot site; it does not seem to be clogged, but I can't say for sure how much gas gets through; I probably put more force to blowing through it than the natural gas flow does.

The trouble shooting guide says to check that all manual gas valves are open, supply tubing and pressures are good, and that the pilot burner orifice is not blocked. Then to check for 24 Vac across PV-MV/PV terminals on module. If voltage is ok, replace gas control, if not replace module. I have no idea what all that means.

Anybody?

Thanks.

Charlie

 

[spishex]

If the spark is working properly and you get no flame then there's not enough gas getting to it. Take a look at it when it's installed to verify that the spark is working when it's actually in the heater. Sometimes the wire to the sparker can short out on the heater housing and spark a few inches away from the pilot.

If all is well down there then you have an issue with gas getting to it. Check to be sure the gas valve is open (I assume it is if the unit fired once or twice).

 

[charlied]

If the gas valve is open (which, considering it was working, it clearly is), and the spark is visible, what would cause a blockage to the gas line? Or what would stop gas from being available for ignition?

(Blew high pressure air through the ignition line, seemed clear)....

 

[jay_k]

Listen for the gas valve to open. There should be an audible click. Check each of the gas burner orifices. The typically unscrew off the gas pipe that leads to the burner. Spiders like to make homes in them Also check the gas manifold pressure with a manometer after the gas valve opens. The label on the inside should tell you how many inches of water, "WC", are required.