Raypak GAS PRESS Error Code
Gas pressure / PIM wiring related error on the XTherm/MVB controller display.
Source: hvac/raypak/47951c62__h-1005a__ryp-xtherm-1005a-2005a-iom.pdf
What does Raypak GAS PRESS mean?
The controller's Error Display lists GAS PRESS with the instruction to check PIM wiring, indicating the control is not seeing a valid gas-pressure or PIM input. The unit cannot confirm acceptable gas supply conditions for a safe ignition sequence, so it flags the error. The manual notes incoming dynamic gas pressure must not be less than the rated minimum for the fuel in use.
Symptoms
- GAS PRESS displayed as the active error on the controller
- Heater will not progress through the ignition sequence
- Possible no-heat condition
- Red fault LED on the PIM
Common causes
- Loose or miswired PIM connections
- Low incoming dynamic gas pressure below the rated minimum
- Closed or partially closed manual gas valve
- Gas pressure switch wiring fault (if equipped)
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Diagnostic steps
Check PIM wiring
Per the manual's Error Display table, inspect the PIM wiring associated with the gas pressure input for loose, missing, or miswired connections.
Verify incoming gas pressure
Confirm the dynamic gas pressure to the gas valve is not below the manual's rated minimum for natural gas or propane.
Confirm the manual gas valve is open
Check that the field-installed manual gas valve near the gas inlet is fully open and gas is on at the meter and the heater.
Reset the control
After correcting the wiring and gas supply, press and release the RESET button to clear the fault.
Observe ignition
Watch the unit complete its ignition sequence and run normally without the error returning.
When to call a professional
Gas-pressure diagnostics involve a manometer, the gas train, and the fuel supply, where mistakes risk improper or dangerous operation. The manual instructs that if overheating occurs or the gas supply fails to shut off you should shut the gas at the service valve, not cut pump power. Any work inside the gas train or on live PIM wiring should be performed by a qualified Raypak service technician.
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Other Raypak Error Codes
Outlet water sensor fault on the XTherm/MVB controller display.
High limit sensor fault on the XTherm/MVB controller display.
Inlet water sensor fault on the XTherm/MVB controller display.
Ignition fault on the XTherm/MVB controller; clear with RESET.
Heater temperature tripped the high limit on the XTherm/MVB controller.
False flame detected on the XTherm/MVB controller display.
Identity card fault on the XTherm/MVB controller; check ID card and wiring.
Internal control fault on the XTherm/MVB controller; reset power, replace control.
Temperature difference between inlet and outlet exceeded the setpoint.
Low 24 VAC power; check power supply wiring and transformer.
Blower speed out of range; check blower wiring and blower.
Unit not detecting enough flow to allow the ignition sequence.