Underfloor heating not working
Check the steps below first — if you\'re not confident, get it fixed safely today.
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Most likely cause & what to check
Check the thermostat or smart controller for the underfloor heating zone — confirm it is calling for heat and set above the current room temperature.
Find the underfloor heating manifold (usually in a cupboard or utility room) — it looks like a series of pipes with flow meters and valves. Check all zone valves are open (handle inline with the pipe = open).
Check the actuators (small cylindrical motors on top of each manifold valve) — they should feel warm to touch when the zone is calling for heat. A failed actuator can be replaced for £15–£30.
Check the system pressure on the manifold gauge — wet underfloor heating is part of the sealed heating system and requires 1–1.5 bar.
Check your boiler is firing and that the circulation pump is running (you should be able to feel vibration on the pump body).
If individual zones are not heating but others are, and actuators are working, the manifold balancing valves may need adjustment. This is a job for a heating engineer.
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