Ravenheat combi boiler help

12 Feb 2009
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United Kingdom
HI, I have a Ravenheat COMBI boiler. for the last couple of weeks I have had to add pressure daily. When the heating is on the pressure goes up to 2.5 - 3.0 bars and when the boiler is not in use it drops down to 0.5. Does anyone have any ideas? There does not seem to be any leaks
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The expansion vessel is ka-put, either lost its charge or diaphragm is split.

is this a big job/expensive? I've only just spent money on it replacing the hot water/heating valve switch thingy!
You can look to see if the expansion vessel has split or has just lost its charge....
Look behind the boiler (look down behind the flue) for a large red 'drum'.... hopefully, but not all ravenheats are easy to get to, there should be a care tyre type of valve - called a schraeder valve.... take the cap off and depress the centre of the valve... if water squirts out, it needs replacing, and this is usually a boiler off the wall job or have a new one piped into the system externally....
However, if just a faint 'pssssst' comes out then you need to recharge the vessel with a footpump. There are numerous sites out there and help topics on here explaning how to do that..... but remember when you are pumping it up, you must have the system open to atmosphere.

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Search FAQ's, all the info is in there for you to check/replace the EV ;)

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