Just moved into a house with central heating that has no room thermostats, but rad thermostats on each rad.

Even with some set to max, the boiler seems to come on for about 1 minute, then go off for about 1 minute, then come on etc. There's a stat on the boiler itself (set to 4 out of 5 at the moment, but I've tried 2 and 3) and a stat on the hot water tank (set to 80 degrees -- but I've tried 60 degrees too).

It wouldn't be so bad if the boiler didn't make a big 'thump, whoosh' every time it came on. But I'm pretty convinced it shouldn't be coming on that often anyway -- seems like there's not enough hysteresis somewhere in the system.

Any thoguhts? I think a visit from British Gas may be in order.

Carl...What you should be concerned about straight away is the thump and whoosh you described as this sounds like delayed ignition of the main burner and this can be dangerous. What is happening is that gas is being sent to the burners and the pilot is not igniting the gas straight away hence the thump when it does light. To be 100% safe as I can only try to help from the information given turn the boiler off and call out a CORGI reg gas engineer, the other problems could then be sorted out. For your information hot water should be stored at 55 degrees anything over this will promote limescale formation.

Mog