Honeywell Error Code E351: Equipment Fault

Severity
Warning
Type
digital display
Estimated repair cost: $75 — $200 (parts + labor)
Warning: Your Honeywell HVAC system has detected an internal fault and shut down to prevent further issues. This requires troubleshooting to restore heating or cooling.

How to Fix Honeywell Code E351

  1. Step 1: Check the air filter. A dirty filter restricts airflow and can cause various issues. Replace it if it's dirty.
  2. Step 2: Reset the system. Turn off the power to the unit at the breaker for 60 seconds, then turn it back on. This might clear a temporary fault.
  3. Step 3: If the error persists after these steps, contact a qualified HVAC technician for diagnosis and repair.

How to Reset Honeywell Code E351

  1. Remove the thermostat from its wall plate.
  2. Remove the batteries and wait 30 seconds.
  3. Reinsert the batteries and snap the thermostat back onto the wall plate.
  4. If the error persists, perform a factory reset through the menu: Menu > Preferences > Restore Factory Defaults.

What does E351 mean?

The Honeywell E351 error code indicates a general equipment fault within your HVAC system. This is a broad error, meaning the control board has detected an issue but needs more information to pinpoint the exact problem. It's like a 'check engine' light in your car – it tells you something's wrong, but not specifically what. This error can affect various components, from the blower motor to the ignition system (if it's a furnace) or the compressor (if it's an AC or heat pump). Because the system has locked out, you won't have heating or cooling until the fault is resolved. Ignoring this could lead to further damage or discomfort.

Affected Models

Replacement Parts

PartOEM NumberEst. Cost
Flame Sensor S8610U3009
Blower Motor
Integrated Control Board

Related Codes on Same Models

CodeDescriptionSeverity
E1 Communication Error Warning
E2 Sensor Fault Warning
E3 EEPROM Error Warning
E4 Short Cycle Protection Warning
E5 Wiring Error Warning
E350 Low Battery Info
E352 Sensor Open Warning
E353 Sensor Short Warning