BoilerTroubleshooting2026-02-26
Radiators Hot Upstairs, Cold Downstairs
Uneven heat usually means a circulation, pump or balancing problem.
When upstairs radiators heat but downstairs stay cold, circulation or balancing is off.
Common causes
A failing pump, sludge, or an unbalanced system can leave the harder-to-reach radiators cold while others heat.
What to do
Balancing the radiators, a pump check and possibly a power flush restore even heat throughout the home.
Key takeaways
- Often a pump or balancing issue
- Sludge can block circulation
- Balancing evens out the heat
- A power flush may be needed
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