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HVAC

How to Fix a Boiler with No Hot Water

Quick Answer

Check the thermostat, check the timer, and check the boiler pressure.

How to troubleshoot a Boiler with No Hot Water

A boiler with no hot water is a frustrating problem. This guide covers diagnosing and fixing common causes.

Step-by-Step Fix

  1. Check the thermostat is set to the correct temperature.
  2. Check the timer is set for hot water.
  3. Check the boiler pressure is between 1 and 1.5 bar.
  4. Check the pilot light is on (if applicable).
  5. Check the diverter valve is functioning.
  6. If the issue persists, call a Gas Safe engineer.

Common Error Codes

CodeMeaningResolution
No hot waterFaulty diverter valve or thermostatCheck diverter valve and thermostat.
Error codeBoiler faultCheck the manual for the specific code.

Frequently Asked Questions

Why is my boiler not producing hot water?

A faulty diverter valve, thermostat, or low boiler pressure.

Can I fix a boiler diverter valve myself?

Only if you are Gas Safe registered.