One Radiator Not Heating When Others Are
Every other radiator is hot, but one stays cold all the way through..
Every other radiator is hot, but one stays cold all the way through.
What is actually going on
Every other radiator is hot, but one stays cold all the way through.
The realistic causes, in order
A thermostatic valve pin stuck down after summer, a classic and easy fix A blocked radiator full of sludge, usually the coolest one on the circuit A closed lockshield left over from previous balancing work
What we test on site
Valve pin movement with the head removed Flow and return temperatures across that radiator against its neighbours System balance across the whole circuit, not just the cold unit
Get one radiator that stays cold diagnosed properly
Freeing a pin costs almost nothing; a sludged radiator needs flushing or replacing, and we'll tell you which it is.
Questions we get asked
Why does one radiator that stays cold affect some radiators and not others?
A thermostatic valve pin stuck down after summer, a classic and easy fix
What normally puts one radiator that stays cold right?
Freeing a pin costs almost nothing; a sludged radiator needs flushing or replacing, and we'll tell you which it is.
Is it safe to keep using the system with one radiator that stays cold?
Draining and refilling any part of a sealed system means re-dosing inhibitor. Skipping that step is what causes the next round of sludge.