Why does the blower run after the furnace cycles off?

When the fan cycles back on while the burner remains off we figure that the heat exchanger is still so hot that even without the burner being on, the air in the plenum heats back up after the fan cuts off, causing the switch to turn the fan back on.

How long should furnace blower run after burner shuts off?





In normal operation, your furnace blower fan should come on 1.5 to 3 minutes after your thermostat calls for heat and should turn off several minutes after the heating cycle ends. Your blower should run constantly until the heating cycle ends.

What causes a blower motor to keep running?

If your fan limit switch is set to AUTO but the fan continues to run without ever stopping, you’ll need to call a professional. Two problems that could cause your fan to run without stopping include: A bad fan limit switch that needs to be replaced. Bad thermostat wiring.

Why is my furnace fan blowing constantly?

Furnace Fan Malfunction Causes



There are three main reasons for your furnace fan to stop working properly and to start running constantly: The blower control is set to the wrong setting. The limit switch is set to the wrong setting. The limit control needs adjusting.

Why does my furnace keep shutting off after a few seconds?

A common reason a furnace short cycles is because the heat exchanger, the part that heats your air, is getting too hot due to a lack of airflow. Once the heat exchanger overheats, it trips the high limit switch, which shuts the furnace down to protect it.

What do I do if my furnace is short cycling?





Contact your furnace repair service before assuming the problem with your furnace is its size. While it may be the cause, there could be another problem with the device. Another common cause of a short cycling furnace is that the furnace itself is overheating and it’s turning itself off to prevent damage.

Why does my blower motor keep turning off?

Dirty air filter(s): If the filter is so dirty that the blower is overheating trying to pull air through it, the blower might stop. When it cools off, it starts again. This is an easy fix. Wrong fan speed: Same issue as above, but a different cause.

What are some possible causes of delayed ignition?

Delayed ignition is caused by moisture building up in the furnace over a period of inactivity. The moisture begins to corrode the firebox which blocks the ports that feed gas into the burners. Should the ports get blocked, the burners down the line fail to light promptly.

Why does my furnace fan not shut off?

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Quote from Youtube video: This is craig migliaccio from aec cyberstack. And today what we're going over is why a furnace blower motor continues to run and blow cold air all through the building. So even when the thermostat is

How do you stop a furnace fan from running?



Set your thermostat to a temperature that’s lower than the current room temperature. This shuts the furnace down and prevents your thermostat from calling for more heat. If the furnace was in the middle of a heating cycle, wait 3 to 4 minutes for the blower fan to stop running.

How do you reset a furnace fan?

How to Find and Reset your Furnace Motor Blower

  1. Step 1: Turn off the power to the furnace. …
  2. Step 2: Remove the blower compartment cover. …
  3. Step 3: Make sure the blower is completely cooled off. …
  4. Step 4: Locate the reset button. …
  5. Step 5: Press the button in (assuming that this is your issue and that the button has popped).


Is there a reset button on a Bryant furnace?



Bryant air conditioners are no different. However, unlike other companies that manufacture air conditioners, the brand doesn’t have a reset button on the air conditioner. You have to reset the device by resetting the circuit breaker in your house.

Where is furnace blower reset button?

Locate the reset button on the furnace and press it to reset the furnace. It is usually located inside the blower compartment on the side of the blower motor. Be cautious as the housing may be hot. If the button is popped up, press it down.

Why will a blower run on the on position and not on auto?

Other Blower Fan Won’t Run Problems



The fan will run and blow warm air but only in FAN or FAN ON mode – delivering heat – but NOT in AUTO mode. This is a bad temperature sensor in the unit; replace the fan limit controller.

Should fan be on auto or on in winter?

The most obvious benefit to keeping the furnace fan on the “on” setting is more even heating and cooling distribution. Heat has a tendency to rise in the home during the winter due to “stack effect,” and parts of the home that see greater sun exposure may also become warmer than the rest of the house.

How do I know if my furnace blower motor is bad?



5 Signs Your Blower Motor Needs to Be Replaced

  1. Weak Airflow from the Vents. This is usually the first indication that you may have a faulty blower motor. …
  2. No Airflow at All. …
  3. Unusually High Energy Bills. …
  4. Strange Sounds. …
  5. Overheating.