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Grant Boilerhouse fault 4

Water temperature low

Oil boiler

What it means

Boiler operates but water temperature remains low, indicating undersized nozzle, low fuel pressure, or heat exchanger issues.

Likely causes

  1. Undersize nozzle
  2. Low fuel pressure
  3. Dirty boiler heat exchanger
  4. Faulty boiler thermostat
  5. Incorrect combustion settings
  6. Dirty fuel filter

Where to start

  1. Check condition of boiler heat exchanger and clean if necessary
  2. Check the boiler thermostat
  3. Check the combustion settings

The full answer, free

  • 28 more checks in order
  • The readings and component tests from the manual
  • How to put it right, step by step
  • The manual page for this fault (page 48), right under the answer
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Safety: Isolate oil and power before you touch the burner. Do a combustion test after any burner adjustment or part change. OFTEC (or equivalent) work only.

From the Grant manual for the Boilerhouse. Check the model on the data plate before you order parts.

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