American Standard lp gas furnace, model ADX060C936CO (hot surface ignitor)

[ectofix]

Galley,

This forum focuses on cooking, food prep, warewashing and refrigeration equipment.

 

Are you bringing this question HERE with anticipation that some food equipment techs also do HVAC?  I’m sure there are some who do, but I expect you’d get more visibility if you posted your question within a forum dedicated to HVAC.

[galley4u]

Thanks for responding!

[alnelson]

When you say 24 volts going through the pressure switch, do you mean you measured 24 volts across the terminals on the pressure switch?

 

When you turned the furnace on the second time and the ignitor came on with no call for heat, did the igniter come on and go off immediately? Or did it stay on indefinitely?

[galley4u]

It may be worth mentioning that when I got this response from Al, the email said I could simply “reply”, but my response did not show up here. This may explain why it may appear many people do not seem to follow up when they get feedback? Just a thought ..

 

When you say 24 volts going through the pressure switch, do you mean you measured 24 volts across the terminals on the pressure switch?

 

I mean that when the switch was satisfied and closed, there was 24V flowing through the switch and back to the board.

 

  When you turned the furnace on the second time and the ignitor came on with no call for heat, did the igniter come on and go off immediately? Or did it stay on indefinitely?

 

Stayed on indefinitely. Thanks!

[ectofix]

galley4u said:

“It may be worth mentioning that when I got this response from Al, the email said I could simply “reply”, but my response did not show up here. This may explain why it may appear many people do not seem to follow up when they get feedback? Just a thought .. “

  Thank you for pointing that out.  Probably my first and most prolific issue I’ve had with this little forum is – the nearly TOTAL lack of feedback from an OP.

 

Regarding your response to alnelson and from my own very limited experience on HVAC systems:

 

NO HSI should stay on.  In a flame management/safety circuit, there’s a logical sequence of events leading up to an ignition trial and following it – depending on the outcome of the trial.  Operation of the HSI is a timed event and correlates directly to the circuit’s expectations to prove flame.

 

Additionally, there obviously shouldn’t be ANY ignition trial if there’s no call for heat.

 

If everything is wired correctly and you have proper inputs from the relevant power sources…then YES, it seems you may have a faulty board.

Did that short at the HSI wire possibly cause that?  In my past experience, circuit protection to prevent damage to a board tends to be an afterthought by most manufacturers (of cooking equipment).  So…control boards DO take the hit and fail due to the controlled circuits shorting out.

 

They’re getting better though.

[alnelson]

I agree.

 

Sometimes when boards get powered up initially they will briefly power all the components, but if the igniter is staying on indefinitely especially with no call for heat, I would agree the board is at fault.

[galley4u]

I do feel that you guys have given me the information I need to move forward, and I really appreciate it. Thank you! I have a new board and a new ignitor coming, and we’ll just hope that the thermostat is still okay!