Boiler losing pressure

[Mattylad99]

I have a Worcester Bosch 28i RSF boiler (circa 2003/4) with the following symptoms;

- Loss of pressure - Now down to 0 bar
- Drips from outside PRV pipe (stopped when pressure at 0)
- When hot water turned on boiler makes excessive noise. This does not happen when boiler is off which would rule out the flow restrictor
- Hot water is OK
- Not tried CH
- Combi shower is OK

I have carried out the following;
- Turned the PRV valve on the boiler - This caused the PRV outlet pipe to drip faster
- All rads bled to remove any trapped air
- Re-pressurised to 1 bar - This eventually went back down to 0

I have investigated this site and the Net and the common suggestions are that this is either, or a combination of, the following;
- PRV (£10)
- Exapnsion Vessel (£53)

Can anybody advise any further on this matter and of the above, which would be the most appropriate course of action to take. Thanks in advance, Matt

 

[steve32]

new prv
check air pressure in expansion vessel

FAQ No (1)

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