Pressure builds in boiler

[tonytimms2]

I have a Worcester Heatslave 12/14 running 6 medium sized radiators in a small bungalow. System runs ok but now and again for no apparent reason the pressure gauge shows increased pressure, the pump motor gets very hot and hot water does not run out of the boiler. If I switch off the boiler off at the mains, release pressure via the pressure valve to 0bar, top up the pressure to 1bar again, switch the boiler back on and in a few minutes the hot water runs in the pipes and through he radiators again. This is driving me mad because there is no pattern to it and just happens now and again, probably once a week. Any suggestions appreciated.

Regards

 

[DustyM]

When you say hot water doesn't run out of the boiler, do you mean from the hot taps, or are you trying to bleed the boiler its self?

 

[RPG 80]

might be an expansion problem you need to get a OFTEC engineer to check it out soonest

 

[Dotty]

might be an expansion problem you need to get a gas safe engineer to check it out soonest

Be much better to get an OFTEC engineer.........

 

[RPG 80]

Be much better to get an OFTEC engineer.........

that'll teach me for skimming threads

 

[dancinplumba]

Be much better to get an OFTEC engineer.........

pmsl

 

[tonytimms2]

Water in the boiler itself gets very hot but although the pump is running (the pump gets very hot) hot water does not come out of the central heating flow at the back of the boiler.

Regards

 

[tonytimms2]

I have checked the expansion vessel and when I press the bleed valve it shows there is pressure. No water escaping.

Regards

 

[kimbo]

The pump might be running but it sounds like its not circulating so check the shaft to see if it is spinning it might be jammed, also check 3 port valve isnt stuck in hot water mode only.