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critical Honeywell

Error Code Proof of Water Flow Alarm

A high-severity alarm indicating no water flow is detected when the water pump or water valve should be operating.

? What Causes This

Water pump failure, blocked water line, disconnected proof of water flow sensor, or water valve malfunction.

How to Fix It

  1. Verify water pump is operating.
  2. Check water line for blockages or kinks.
  3. Verify proof of water flow sensor connection.
  4. Contact service personnel.

Source: page 119 of the official manual

From the manual

Manual page 119 — Honeywell error Proof of Water Flow Alarm

This error code appears in:

Honeywell Home Thermostat