One of the most common failures with high efficient furnaces in Winnipeg will show up as a Pressure switch fault code.
A pressure switch fault code can be one of the most difficult to verify.
Here is a brief description of what normally happens within the venting system of a high efficient furnace:
- After proving ignition, the draft inducer motor runs and creates pressure within the venting system.
- Pressure switches are connected to the vent system to confirm pre-ignition status and adequate pressures during the heat cycle.
- Pressure switches communicate with the circuit board to maintain proper start up and monitoring of the vent system.
Most of the time (80% or more) this fault code is an indication of inadequate (low or high) pressure levels in the venting system and is not in fact a faulty Pressure switch.
- Snow, frost or ice build-up on the outside vent pipes will change the pressure level within the system and the pressure switch will do its job and shut the furnace down.
- A weak or worn draft inducer will eventually produce less pressure and again, the pressure switches will do their job and protect the furnace.
- Blockage in the condensate trap or drain can also introduce a pressure switch fault.
- Poorly installed vent pipes that are leaking or improperly sized can cause a pressure switch fault as well.
- Lastly, there have been a few cases with some furnace models where a blocked secondary heat exchanger or a failing circuit board will display the pressure switch fault
It is important to understand that Pressure switch are safety devices that should never be bypassed or tampered with.
For your safety, call a service professional and have the proper diagnosis confirmed. for your Pressure switch