Giant Error 4: Pressure switch stuck open
The pressure switch remained open longer than five seconds after the power venter was energized, so the control cannot prove proper venting/airflow. (Note: the blower high-limit switch is in series with the pressure switch, so a tripped high limit can also cause this.) We diagnose and repair it across Greater Vancouver — same-day and after-hours.
The pressure switch remained open longer than five seconds after the power venter was energized, so the control cannot prove proper venting/airflow. (Note: the blower high-limit switch is in series with the pressure switch, so a tripped high limit can also cause this.)
Giant fault codes can vary by model and series. Use this as a guide — the same code can have more than one cause. Our Technical Safety BC–licensed technicians read the code, confirm it against your unit's manual, and diagnose the true cause before any repair.
Likely causes of Giant error 4
- Obstruction or restriction in the air intake or exhaust flue
- Pressure switch tubing disconnected or not properly connected
- Pressure switch wiring incorrect
- Blower high-limit switch tripped (in series with pressure switch)
What you can safely check
- Check that the outside intake and exhaust vent terminals are clear of snow, debris, lint or nests
- Confirm nothing is blocking the unit's air intake openings
Beyond these checks, do not open the unit or touch gas/electrical parts — BC law requires a licensed gas fitter. Call us for a proper diagnosis.
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Parts often behind Giant error 4
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Giant Error 4 Repair Across Metro Vancouver
Frequently Asked Questions
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