Coleman Evcon DGAT056BDO

[bdozer]

My daughter has a Coleman Evcon DGAT056BDC furnace in her modular home. She had a lighting strike that knocked out her PC monitor and DVD player earlier this summer.
She tried to fire the furnace up last night and it wouldn't light. I went over to look @ it today. The combustion fan started fine, I could see the ignitor glow, but no flame. I put a meter on the 2 leads to the gas valve and am not getting any voltage, AC or DC, to it . Would this lead you to believe the ignition controller is no good ?? Its a Robertshaw HS780-34NR-306A.
Thanks

[Robert]

Hi,

When ignitor glows, it glows for approx. 35 seconds. Then the Valve terminal on ignition module should energize the gas valve for 6 seconds.


Start the call for heat, let booster motor run, centrifugal switch closes sending 24vac to TH terminal on module.

TH to GRND = 24vac

After 15 second purge cycle,Ignitor glows, watch for approx. 35 seconds, then see if module sends 24vac to gas valve for 6 seconds.

VALVE to GRND = 24vac.

IF all is ok up to the 24vac going to gas valve and that does not happen, module is bad.


Again, if you get 24vac across TH and GRND, but do not get 24vac across VALVE and GRND at appropriate timings, module is bad.


Ignition Module # 1474-0061/A can be seen and ordered through PayPal if needed from right side of page here :

http://www.mobilehomerepair.com/ColemanGas.html



Take care and best wishes,
Robert

[grfisher]

Concerning your comment in this area.....
"Again, if you get 24vac across TH and GRND, but do not get 24vac across VALVE and GRND at appropriate timings, module is bad."

I have the electronic ignition module with the EVCON 1474-004 that lights, fires and intermittantly shuts valve off during run cycle.
I have monitored the TH side and maintain 24-26 volts even during shutoff.
But when monitoring the valve terminal of the ignitor-- it drops to zero when the valve shuts off.
Again TH side never drops.
Does this intermittant drop mean the ignitor is bad....?
or could it be something else?
The fan blower is up and running....
and exhaust fan shuts on once the valve closes.
Anything you can offer? It seems my unit eats ignitors .
I have replaced 3 in 19 years.

[Robert]

Hi,

Please post your questions in a new thread. We keep each thread to original poster to keep down confusion in following the questions and answers.


Thanks,
Robert