7H-04 — Water flow problem during domestic hot water production

What does 7H-04 mean?

This code signals a water flow issue specifically when the unit is trying to produce hot water for domestic use.

• Kinked or blocked hot water pipes
• Issues with the hot water circulation pump
• Sediment buildup in the system

Click steps to track your progress.

1. 1

   Verify hot water taps are fully open.

2. 2

   Check for obstructions in the hot water pipes.

3. 3

   Listen for the hot water circulation pump running.

4. 4

   A licensed installer may need to flush the system.