We have just had our kitchen ripped out and after 9 weeks of sheer hell, we are getting back to normal. My combi boiler on the other hand feeds me hot water when i want it, but, when the thermostat is triggered for the central heating, the boiler makes such a grunting noise and vibrates terribly, like it's going to blow itself off the wall. Then it shuts down. Has anyone got any ideas? Someone has mentioned a valve may not be working as it should (the three way one, 1 x water, 1 x heating, 1 x both).

Michael Lomax, June 2008

have a problem with low water pressure, ive toped up the cold water into system and it has dropped to below 1 bar, ive checked all the radiators (no leaks),there isnt any water coming out of the overflow pipe, Has anyone any ideas?? Thank you

martin, September 2008

For some reason, the boiler can't disperse the hot water that it is generating - hence the rumbling noise of the water boiling before it shuts down. Some things to check....is the circulating pump running? Is there a wheel valve that connects the flow and return pipes together (the bypass) shut?
Are the radiators full of air? Has the boiler about 1 bar of water pressure? There may also be an air bleed valve in the top of the boiler - on one of the 22mm copper pipes usually - that should be bled. Try operating any zone valves by hand to see if hot water surges through into the radiator system.

John, June 2008