Radiators cold or boiler not heating
Some or all radiators stay cold, or the boiler keeps locking out.
What you're probably seeing
Some or all radiators stay cold, or the boiler keeps locking out.
Likely causes
- Air trapped in radiators.
- Low boiler pressure.
- A failed circulator pump, valve or ignition.
Safe checks you can do now
- Check the boiler pressure gauge against the label.
- Bleed radiators that are cold at the top.
- Reset once per the manual; don't keep resetting.
When to call a pro
It locks out again, leaks, or radiators stay cold.
General information about common causes, not a diagnosis of your home.
FAQ
Quick answers
Who fixes radiators cold or boiler not heating?
A heating and cooling company. Call (844) 511-3573 to connect with an independent local heating and cooling company.
How much does it typically cost?
Boiler repair: $150–$700 (HomeGuide 2026 national ranges). Your pro sets the real number after seeing the job.
When should I call?
It locks out again, leaks, or radiators stay cold.
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