My boiler often drops in pressure and the red low pressure light comes on. I usually turn the black tap to let in some water and its ok again. I have had 2 plumbers out to fix this before and it has now gone again. The gas in the boiler is lit but I cannot get the low pressure light to go off so have no hot water or heating. I would be really garteful for any suggestions
Many Thanks

Charlotte, September 2007

how do i get the low pressure light go off my boiler

nathan, July 2010

> if you disconnect one of them it bypasses the pressure switch

thats how not to do it.

if your boiler has lost pressure open the filling loop and top up
if it keeps loosing pressure check the prv if ok then you have a leak somewhere on the system.
maybe a rad or pipework under the floor boards.

hi-spec plumbing, September 2007

i had that problem before .

If you take the white cover off, then the pcb will be in front of you with a small screw in the right hand corner, undo that and let the unit hinge towards you.

behind it you should see a valve with two yellow wires coming off the end, if you disconnect one of them it bypasses the pressure switch and you should be able to get hot water, atleast. make sure the pressure is good

i dont know what the cure is that is what i am trying to find out myself.

i am not a plumber i tried a few differnet things and it seemed to work for me it got me out of a hole.

damo, September 2007