- Condition: The dryer has detected too high of gas pressure to the burner.
- Alarm Action Taken: COOL DOWN
- Component: Gas Pressure Switch.
- Location: On the fuel trane at the base of the dryer after the Modulating motor and butterfly valve.
Tools Required for Service:
- Voltage/continuity meter
- Small standard blade screwdriver (to remove cover and wiring terminals inside)
- “Shorty” flat blade screwdriver (to adjust setpoint)
Tech tip: (Has a scale reading in Pounds lbs)
The high gas pressure switch is a microswitch based device that monitors the gas pressure allowed to the burner. It normally can be identified by being one of two pressure switches located on the fuel trane at the base of the dryer with a glass cover with a scale viewable inside.
If the vapor regulator allows too much gas pressure through, the microswitch opens up its contacts and triggers the alarm. To adjust the setpoint, remove the right-hand screw in the mounting clip that holds the glass face cover on. Behind the clip is the adjusting screw. Adjust the screw in or out to change the setpoint.
Potential causes of this alarm condition:
- Improper vapor regulator setting (too high)
- Improper “Low Fire” setting of butterfly valve creating surging of the gas through the valve causing the microswitch inside to bounce
- Switch setting too low
- Faulty switch
- Poor or faulty wiring connection