Worcester Boiler

[heleneb]

Hi - completely new to this, and probably going to renowned for asking daft questions, but anyway - here goes!
I have a Worcester 240 combi boiler and over the last week, the mains water pressure has been low which has meant that I have not been able to get any hot water - the heating has worked ok, but no hot water - is this normal?
But also, the main problem I have now is that the mains water pressure has returned to what I assume is normal, but the pressure gauge on the boiler is now above 2.5 ... and here's the daft part - I have no idea where the pressure relief valve is.
I have the manual, but it's not at all specific and I'm not sure whether I'm supposed to remove some of the inner covers rather than just the main outer one. The only valve type thing that's obvious is the gas valve which if I turn, just puts out the pilot light.
Am I missing something really obvious ... I'm a bit worried that the system will explode if I don't try and get the pressure down a bit.

Cheers
Helene

 

[ogoshi]

Hi helen,sorry i didnt see your post earlier.
Low mains pressure will result in no hot water, as your boiler needs a minimum of 0.6 bar to activate it for domestic hot water.Once the mains pressure returned to normal your dhw was functioning again it should not have altered the the pressure on the gauge which is for the central heating.That pressure can only be increased by using the filling loop(silver flexi pipe from cold main to boiler,and a black plastic lever tap on one end.)Does the pressure gauge show over 2.5 when the boiler is cold or hot.?
It should show 1.5 when cold and not over 2.5 when hot.
If its 2.5 when cold then as you said you need to reduce the pressure via the relief valve.this is located in the bottom section of boiler,to the right of center.To get to this you should remove the outside/front of the boiler by
lifting and pulling forward,then look inside,bottom,just off center you will see a red or black plastic knob,turn this a little bit and watch the pressure gauge untill pressure drops to 1.5(if you turn to far it opens then closes the valve,you will understand once youve done it).
you must do this when the boiler is cold to get an accurate gauge reading.Finnally dont worry about the boiler blowing up under to much pressure as once the gauge reaches 3 bar the safety valve opens and discharges all the water outside via the discharge pipe.
hope this helps.

 

[heleneb]

Hi ogoshi
Many thanks for your help - I did a lot of bleeding of radiators over the weekend, which helped, but now I know where the relief valve is, I should be able to sort it properly.
Cheers
Helene