furnace fan not working on auto

5490 satisfied customers. It runs fine when the furnace calls for the fan.

Furnace Or A C Fan Won T Stop Running What To Check If The Blower Fan Will Not Stop

Other Blower Fan Wont Run Problems.

. It could be two things. This is a bad temperature sensor in the unit. We can turn on the fan manual and that works OK.

Once you have confirmed that you have a useable on setting we will discuss what the difference is between the two. I am having sort of an odd issue. The fan will only turn on when the thermostat starts the.

According to the professional it seems to be caused by the defective heat sensorthermostat on the furnace unit. 2- Fan limitcontrol is not closing. Replace the fan limit controller.

Meanwhile the Circulate setting is a hybrid and auto that keeps the fan running throughout heating cycles and then again for a few minutes every hour even when the furnace is off. The fan should come on right away. One diagnostic step that can be taken is to put the Fan switch to the On position at the thermostat.

My furnace stopped working a few days back. If it has control board then it a relay on the board. The burner comes on but the auto fan wont come on.

That said it does work when I put it into Fan On mode orand when I put it into CoolingAir conditioning mode. If so it should come on automatically when the burners are lit. I replaced the capacitor thinking this might be the culprit no change.

Another key difference is that the circulate. In AUTO mode the furnace will heat up but the fan wont run the heater then reaches the HI LIMIT and the. There is another limit switch in the blower area L140-40.

Furnace is a Bryant model CNPVP6024ACAAAAA. It may be necessary to leave the fan in the On position so the heat can continue to operate until the problem is resolved. Silver box with a big dial w 3 tabs settings If the fan runs with the t-stat switch fan to ON you got power.

I had a basic Emerson thermostat White Rodgers 1f86-0244 installed a few months back and cooling functions worked fine. When fan is switched to ON the furnace works. The furnace auto setting will have the fan come on after the burner has been running for a while.

Its in heating mode. It can be a fan relay switch or limit. The fan will run and blow warm air but only in FAN or FAN ON mode - delivering heat - but NOT in AUTO mode.

If so check whether the fan is switched ON on the thermostat. The furnace blows hot air only in FAN mode. When the fan is switched to AUTO it ignites but the fanblower doesnt kick in and after a short per.

After resetting breaker I tried again. When I put the thermostat to HeatOn position fan to Auto and raise the temperature to 80 degrees room temp was 50 degrees there was no response from the furnace. You be able take board of bracket and see if burn up on backside.

The main difference is that the fan ON setting means that the fan is set to run as long as the furnace is switched ON. I currently have an issue with fan not turning on automatically when in Auto Fan mode while in Heater mode. With fan in auto I hear a soft hum but it does not ever try and cycle on.

Oct 7th 2015 1120 am. Manual fan control on t-stat not working but Auto works. I replaced the limit switch L170-40 and still have the same problem.

My furnace blower turns on and off just fine with the t-stat fan switch in the auto position but if I want to just turn the blower on manually it wont work. Furnace Repair Things are unusually cold and the gas furnace. It doesnt come on if in auto mode but if I put it in the on mode the blower comes on and I have heat.

When the mechanical thermometer is switched to AUTO I could hear the click sound from the unit however the FAN does not start blowing the hot air at all. Received 0 Votes on 0 Posts. Things are unusually cold and the gas furnace quit.

There is no battery in the thermostat. Otherwise the heat0activated switch is likely bad and needs repair or replacement. Everything goes as it should except when time for blower fan to come on.

1- Heating speed winding on the motor has gone out. Upvote 11 12-29-12 0113 PM PJmax. Check whether your furnace uses a heat-activated blower fan.

If it does not than this is not an option for you currently. If the fan operates this would indicate that the problem is most likely something other than the fan motor itself. You can leave it on to get heat.

The unit gets gas but the fan does not blow and so the flame shuts off after a few seconds. The thermostat clicked and heat was flushing which means it was sending a signal to the furnace to kick in but the furnace would not start. Troubleshooting I found it worked when I switched the fan to on position.

The fan works fine on air conditioner auto.

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