Combi boiler pressure lost

mrochester

mrochester

mrochester

Soldato
Joined
29 Sep 2003
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Location
Newcastle upon Tyne
Hi all

My combi boiler has stopped giving me any heating or hot water, and is showing 0 pressure. My sitting room radiator has been gurgling a lot recently when the heating has come on, but otherwise everything has been OK. Does anyone know what could have happened? Water still flows through the boiler fine when I turn a hot tap on. Would the central heating pressure being too low cause the whole boiler to stop working (i.e., hot water too?)

Many thanks for any advice.

Michael.
 
As brummie said, Use the filling loop, 2 small valves to slowly top up to 1 bar.

see if it holds.

if the gauge doesnt start to rise after a minute or so, you might have a GUSHER.

Al
 
My combi boiler has a valve underneath and a hidden key to operate it with. Look in the manual (or if don't have a manual, google it).
 
combipress.jpg


Most likely wont be in the same place but shows what you are looking for, its usually in the general area underneath the boiler.
 
Thanks all. It's a Baxi 105HE. If anyone can guide me exactly WHAT tod, it'd be really appreciated. Why would the pressure suddenly drop, and is it the heating system that would make the pressure drop? I bled a radiator a couple of months ago.
 
mrochester said:
Thanks all. It's a Baxi 105HE. If anyone can guide me exactly WHAT tod, it'd be really appreciated. Why would the pressure suddenly drop, and is it the heating system that would make the pressure drop? I bled a radiator a couple of months ago.
Click to expand...

Are you on a pay as you go gas system witha topup card? Letting it run out can cause this.

If you find the pressure valve like the one in the picture above, turn it and keep an eye on the pressure gauge, it should start to increase and then slow when its reached the ideal pressure (usually between 1.2-1.7). Close the valve, reset the boiler and try the heat again.

Edit - Keep an eye on the pressure over the next few weeks/months, if it drops quite quickly then you may well have a leak.
 
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Swifty55 said:


Uploaded with ImageShack.us

no.4 and 2

open up until the gauge reaches 1.5 then turn both off. be careful not to over fill.
Click to expand...
^^Agreed^^

OP.....do not fill above 1.5 bar.
Bleeding your radiators will cause this and you don't need to draw off much to drop the pressure below the pressure needed to make the boiler work
Combi boilers can also loose pressure even when there is no leak as they can vent internally.....this is normal and happens more so in the summer when the boiler is not being used for central heating.
When the pressure is too low the boiler will stop working even for hot water......find the filling loop and fill to 1.5bar and it will be good to go.
 
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sounds like you have air in your system, bleed all your radiatiors and then there will be a feed into the boiler for your heating loop which will have a tap of sorts on it, that will re-pressurise the system...
having said all that, if the hot water is not working either i'm not sure that's the problem!
 
If the radiator is gurgling it may be full of air - you may need to bleed the air off each radiator before you repressurise?
 
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