Reliance Pressure Switch or Air Proving Switch Fault

Reliance power vent water heater fan runs but burner does not ignite

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Failed pressure switch, Blocked vent or intake, Disconnected or cracked pressure tubing, Condensate in pressure tube

How to Fix / Troubleshooting

Safety first: Turn OFF power and gas. Do not operate with suspected venting issues due to carbon monoxide risk.

Steps to check:

  • 1. Inspect venting: Check the vent and intake terminations for obstructions. Verify vent length and configuration meet Reliance specifications.
  • 2. Check pressure tubing: Locate the rubber or silicone tubing from the fan housing to the pressure switch. Ensure it is connected at both ends, not cracked, and free of water. Drain any condensate and reattach.
  • 3. Test switch operation: With power ON and a call for heat, the pressure switch should close when the fan runs. A technician can test continuity across the switch. If it does not close, replace the pressure switch.
  • 4. Verify fan performance: Ensure the fan is running at full speed and not obstructed. A weak fan may not create enough pressure to close the switch.
  • 5. Replace pressure switch: Install a new Reliance-specified pressure switch if the old one fails continuity tests.

Note: Never bypass the pressure switch; it is a critical safety device.

Advertisements

Repair Difficulty

Hard 4/5

Required Part

Draft Inducer Pressure Switch
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements