Baxi
DHW Temperature Instability
Hot water runs hot then cold or fluctuates in temperature when taps are used
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
Partially blocked Baxi plate heat exchanger, Faulty DHW NTC sensor, Flow restrictor or inlet filter blocked, Modulating gas valve not responding correctly
How to Fix / Troubleshooting
Safety first: Risk of scalding from sudden temperature changes.
User checks:
- Ensure the cold inlet isolation valve to the boiler is fully open.
- Clean tap aerators and shower heads to remove limescale that may affect flow.
- Run a single hot tap fully open rather than multiple taps partially open to stabilise flow.
Professional actions:
- An engineer may remove and chemically clean or replace the plate heat exchanger, check the DHW NTC sensor, and verify gas valve modulation.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Plate Heat Exchanger
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements