PDA

View Full Version : Carrier furnace flame (only) cycling


Bob Piccinini
Mar 16, 2009, 10:01 AM
I have a Carrier 58GS furnace. It appears to be operating fine until I stood next to it.
The gas flame comes on and off about every 5 seconds. This is not to be confused with short cycling. The blower is running as it should be and at the appropriate times. Thought before I dug into it, the forum may already have the answer.

Thanks for any help,

Bob

wmproop
Mar 16, 2009, 09:10 PM
Try cleaning the flame senser,, is located near the burners,don`t confuse it with the igniter

Bob Piccinini
Mar 16, 2009, 09:28 PM
try cleaning the flame senser,,,,,is located near the burners,don`t confuse it with the igniter

Thanks wmproop, I'll give it a shot.

white732
Mar 16, 2009, 10:17 PM
Is your Carrier 58GS equipped with a "standing pilot" ignition system, or does your furnace have a "electronic spark ignition"system?

Bob Piccinini
Mar 17, 2009, 04:19 AM
Is your Carrier 58GS equipped with a "standing pilot" ignition system, or does your furnace have a "electronic spark ignition"system?

Electronic Spark, I miswrote earlier, it is a 58DR

hvac1000
Mar 17, 2009, 05:45 AM
If you have a 3 wire pilot that can be the cause.

white732
Mar 17, 2009, 05:52 AM
Bob, your pilot assembly would be the first starting point, it's the cheapest and first place to start. After 20 years it's the primary cause for your problem.

white732
Mar 17, 2009, 05:55 AM
Bob, I miss wrote. I have retired with 20 years in the field and found your type of pilot will cause your problem.

wmproop
Mar 17, 2009, 10:21 AM
Quote;;The gas flame comes on and off about every 5 seconds.

I understood this to mean the pilot was working,, but the flame not staying on in the burners

wmproop
Mar 17, 2009, 10:23 AM
Guess I understood the pilot was working but the flame in the burners was going out every 5 seconds

Bob Piccinini
Mar 17, 2009, 11:09 AM
guess I understood the pilot was working but the flame in the burners was going out every 5 seconds

The above quote is correct. I cleaned all connections along with the flame sensor. It is working for now. Looks like it is the pilot assembly causing the problem. Won't hurt for me to get a new one regardless. Thanks for all the help and rapid responses. First time on this forum and it was a great experience.

Bob

hvac1000
Mar 17, 2009, 12:01 PM
The old 3 wire pilot will allow contact for a few seconds then drop out the gas valve then make connection again. This has been a longstanding problem with the 3 wire pilots. Years ago we used to adjust them in the field but no more just replace. All during this time the pilot will be on.