Carrier GFA Runs for 6 min turns off and restarts

[ron997]

Our Carrier 58stx070-12 installed in 2005 is acting up this season.
it has a new filter

It starts normally when the therm tells it to start and runs for about 6 min. 30 sec. Then the fan shuts off, the draft inducer motor starts up immediately, a short time later the burner ignites and fan starts normally for another 6 min. 30 sec. when it does it again until it reaches the temp it's supposed to turn off at then it turns off normally

Since it starts right back on I'm assuming the therm is working ok and still telling it to turn on but something in the heater is turning it off. Am I correct?

Any ideas what problem may be?

Thanks, Ron

[HayZee518]

take a look at the heat anticipator setting on the thermostat. should match or come close to the burner amps.

[ron997]

It's not the stat, I bypassed it and it's still going it.

[hvacwiz]

High limit switch tripping or condensate trap plugged maybe.

[Centurian]

carrier GFA

I'm not a furnace man.. but I've had problems with my furnace starting and stopping..high majority of the time it's the flame sensor that needs cleaning..remove and clean with steel wool..don't be fooled if it looks clean as paul pointed out... a film forms on it which can actually give a false reading

[paul52446m]

GFA Runs for 6 min turns off and restarts

Our Carrier 58stx070-12 installed in 2005 is acting up this season.
it has a new filter

It starts normally when the therm tells it to start and runs for about 6 min. 30 sec. Then the fan shuts off, the draft inducer motor starts up immediately, a short time later the burner ignites and fan starts normally for another 6 min. 30 sec. when it does it again until it reaches the temp it's supposed to turn off at then it turns off normally

Since it starts right back on I'm assuming the therm is working ok and still telling it to turn on but something in the heater is turning it off. Am I correct?

Any ideas what problem may be?

Thanks, Ron

When you say that the fan turns off after 6 min., is this the furnace blower or the inducer fan? If your problem is that exact on the timing every time then it sounds like a problem in the electronic board. Almost sounds like the fan relay in the board is dropping out I would have to test powers on the board to know what is going on when it stops.
One thing you need to check is the 120 volt power and the 24 volt power on the board after it goes through the stat. These electronic boards are very
touchy when it comes to the 24 volt power If it drops to 23 or 22 volts then you can have a problem. You need to have a tester on it so you will see if the power goes down just before it stops. Make sure your line volt is up to 117 to 118 volts. You would be surprised how many problems i find because of low voltages. Paul