Why does my HVAC not shut off?

Why does my HVAC not shut off?

Your HVAC fan should turn on and off with the rest of your heating and cooling system. Common causes for fans not turning off when they should include faulty thermostats, bad wiring, and stuck relays. These problems are not easy DIY repairs and should be left to an HVAC professional.

What should I do if my air conditioner is not shutting off?

Check the fan settings on your thermostat – the toggle should be in the AUTO position so that the fan only runs while the air conditioner is on. If the thermostat fan setting is ON, move it to AUTO – with the temperature set above the current room temperature, the thermostat should tell the air conditioner to shut off as well as the fan.

Why does my furnace blower fan not shut off?

Perhaps there is a defective fan limit control or fan relay control switch. Sometimes my blower fan won’t shut off for a while. It will work for half the day and then the other half of the day it will not shut off.If I flip the breaker off and right back on the fans stays off until the next cycle.

What to do when your furnace won’t turn off?

Turn your thermostat’s fan to AUTO or OFF. This will help you make the most of your troubleshooting later on when it comes to your blower motor. If your furnace is still running hot after doing this, you will be able to rule out some common culprits. Finally, you should check the wiring of your thermostat.

What to do if your a / C fan won’t turn off?

At the room thermostat: the FAN-AUTO-OFF or FAN ON/OFF switch on the room thermostat should be checked. The fan control should be set to AUTO. You can try turning the switch to OFF too. Other snafus such as a shorted thermostat wire can also cause the A/C or warm air furnace fan to run continuously. at THERMOSTAT WON’T TURN OFF. 2.

What to do when a furnace blower won’t turn off?

On the whole, the temperature control switches cannot be adjusted and are to be changed if they are defective. In case the furnace blower does not turn off and it is not bringing cold air, the furnace is still lit. If the furnace is still lit, do not turn off the blower. Lower the thermostat in order to stop the furnace.

What to do if your air conditioner won’t turn on?

There is usually a fan limit control in the air handler that turns the fan on or off depending on air temperature sensed in the plenum just above the heater’s heat exchanger. If the fan won’t stop on your unit look for one of the controls described above on this page and that can be used to manually turn the fan on for continuous operation.

Why does my a / C blower fan keep running?

There are some reasons (explained at BLOWER FAN CONTINUOUS OPERATION) to leave the blower fan on continuously for long periods, such as to use an air filtering system to improve indoor air quality. And in some buildings we may run the blower continuously for more even or better conditioned (heated or cooled) air distribution.

When does the HVAC fan turn on and off?

In normal operation, when your thermostat is set to “auto,” it will tell the blower fan plus the heating or cooling components to turn on and off at the same time when the desired temperature is reached. In many systems, the blower fan runs a minute or so before heating or cooling begins and ends to get air flowing.