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What would cause a pressure switch to not close?
If the air intake or exhaust is clogged with debris, the pressure switch can remain in the OPEN position. This is because blockages prevent the inducer fan from creating negative pressure. A furnace pressure switch stuck open is a common problem for many homeowners.
What is a combustion air switch on furnace?
The airflow switch is a burner/boiler safety device that proves (makes sure) that the combustion blower is running and providing the minimum amount of air pressure for safe light off, before we try to light off the burner.
What is a combustion air pressure switch?
A furnace pressure switch is an automatic safety feature located near the motor. It shuts the furnace down if it senses negative pressure created by the draft inducer motor. This protects your home from dangerous backdrafting, which is when exhaust fumes are reintroduced into the system.
Can I run my furnace without a pressure switch?
Without the pressure switch, there is the potential for exhaust gases to fill the living space if the furnace malfunctions. A pressure switch that fails to turn on could be caused by a number of problems, including: Failure of the draft inducer motor.
Are furnace pressure switches normally open?
The pressure switch is a normally open switch that closes upon the manufacturer’s specifications for required negative pressure. If the inducer turns on and is working normally, the furnace pressure switch should activate. There’s no time lag on this either. The inducer motor creates this draft quickly.
Why is my furnace’s air switch not closing?
The most likely causes for your air switch’s failure to close are: If the flue pipe is blocked, your furnace will likely face problems venting out combustion gases. As a result, it can cause your air switch to fail and remain open. An obstructed flue pipe isn’t unusual.
What does the air switch do on a furnace?
The furnace pressure switch, aka air switch, is a safety measure device found near the draft inducer motor. Its job is to ensure that the furnace only works when the venting air pressure is appropriate. So, if the display shows this error ‘combustion air switch failed to close’, chances are that your furnace isn’t functioning at all.
What to do if your combustion air switch fails?
A combustion air switch can fail if the air hose detaches, and you’ll need to reattach it. Turn off your heater and replace the air switch if it is outdated or broken. Read on through this guide to learn more about the ‘combustion air switch failed to close’ error, and learn ways to fix it once and for all.
What happens if my furnace flue pipe is blocked?
If the flue pipe is blocked, your furnace will likely face problems venting out combustion gases. As a result, it can cause your air switch to fail and remain open. An obstructed flue pipe isn’t unusual.