Gas furnace is running hot/cold intermittently. I had 4 repairmen whohave failed to find the problem. A new ignitor module did nothing. Cold air will blow nonstop with no flame being ignited. All of sudden it will spark and ignite then run normal for a period. All electronics check out good when running with heat. Have not been able to catch it malfunctioning.

It is very hard to tell what the problem could be with a NO NAME and NO EXACT MODEL NUMBER unit since there has been 5,327 different units built since 1970 or so.

It is very hard to tell what the problem could be with a NO NAME and NO EXACT MODEL NUMBER unit since there has been 5,327 different units built since 1970 or so.

Sorry: It is a Central Environmental Systems gas furnace no longer
Manufactured. It is over 15 years old Model P-HCD16N08201A.
It uses a Honeywell universal spark ignitor module with 2 relays and Honeywell fan limiter switch.

Can you do another few favors.

Post the honeywell p/n and the link to the module instructions if you can.

Post a picture of the pilot area using go advanced/manage attachments.

The ignitor module is a Honeywell S8610U. When the gas fails to ignite. The module blinks a code
6+2 (5 minute delay then it will retry ). When the flame ignites it burns strong blue. Very clean.
The furnace is in a crawl space making photos difficult. Ignitor manual customer.honeywell.com/Techlit/Pdf/68-0000s/68-0135.pdf