The boiler seems to be heating in bursts. The main burner is only lighting for a few seconds and then shuts off. This continues until the remote room stat turns off the boiler and the house is warm. This does not occur during the hot water demand.
No fault lights are illuminated and the pressure in the system is fine
Some of these models have a filter fitted in the return pipe, may be as simple as cleaning it (Or removing it - Hint hint) as they often cause issues....
Alternatively; it could be your heating thermistor....
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