F6
Peerless Line Voltage / Power Supply Fault

Boiler shows F6 and locks out; may be labeled 'Low Voltage' or 'Line Error'

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

Low incoming voltage, loose power connections, shared neutral issues, failing transformer

How to Fix / Troubleshooting

Safety first: Turn off power at the breaker. Electrical work should follow local codes.

Steps:

  • Check supply voltage: With a multimeter, verify that the boiler is receiving the correct line voltage (typically 120 VAC) at the service switch.
  • Inspect connections: Tighten all line voltage and neutral connections in the boiler junction box and on the control board.
  • Check transformer: Measure the low-voltage output of the boiler's control transformer. Replace if output is low or unstable.
  • Dedicated circuit: Ensure the boiler is on a dedicated circuit and not sharing neutrals with other loads that could cause noise.
Advertisements

Repair Difficulty

Hard 4/5

Required Part

Control transformer
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements