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I do not have the model number with me...It is an old unit most likely from the 1980s to early 90s ... There is no light on the board...What is occuring is the gas control valve shuts on and off, basically short cycling. My question is could a faulty gas control valve short cycle?
Its an old model, no light on the control board...I did test everything with a meter, as I mentioned the gas control valve short cycles, basically the power goes on and off....could a bad gas control valve coil short cycle or would something else cause the valve to short cycle?
I did check the volts on the gas valve and it does drop out, at times it drops out for a second or 2 and other moments it drops out for a longer period of time...Being that it is an old model it only has a one limit switch with a fusable link.
When I jumped out the limit switch the gas valve was still short cycling, I have already checked the ac coil and it is clean...is it possible that the gas control valve itself is the problem?
Still having the same problem...Here is the model number of the furnace 394gaw036075...I jumped out the limit switch and still the gas control valve continous to short cycle.
I have seen that video before I messaged you on here the first time. However the video still doesnt explain to me why the gas valve short cycles so often, in most cases the gas valves will close and reopen so fast that the flame is still burning and at other times it will close and the flame goes completely out and then within a few more seconds it reignites. Basically the amount of time between short cycles are random, they can vary from 1 second to several seconds
The circuit board is new, I just changed it last week ...I did check the pick and hold terminals and its not losing from both at the same time.
I cant do that now I am not at the location where the unit is..but can you tell me what I need to check for to determine if I have a faulty gas control valve?