A pressure switch senses pressure within the flue system.
Trane gas furnace pressure switch error.
The furnace is working ok.
The sensor closes when the furnace kicks in and allows heat to enter into the home.
Trane xr90 furnace error code indicates the pressure switch.
When a pressure switch error occurs the system will shut down and no warm air will enter the home.
There s a motor engaging but after 5 speed ups the system disengages with the 3 flash error code for the inducer fan or pressure switch.