Drop in combi water pressure - could it NOT be a leak?

[GH blackpool]

Hi there (again)

Just another question.

My combi quite regularly (weekly) needs the water pressure topping up to keep it at 1.5 (after it drops to about 1.1/1.2.)

I suspect a leak but from all the pipes I've been able to access, there is nil to be found.

that of course isn't to say that the inaccessible pipes aren't leaking, but could there be another cause?

thanks again.

 

[chrishutt]

It would help if you could identify your boiler!

 

[GH blackpool]

Ah yes , sorry - it's a Ravenheat RSF82ET (groan).

Thanks Chris

 

[whistler]

Expansion vessel could need pressurising. If the pressure is low in the EV, pressure can build up when the system gets hot and force open the pressure relief valve to expel some water. When the system cools again, the pressure will be low. You top up the pressure and the cycle repeats.

 

[GH blackpool]

hmmm, thanks Whistler.

How doth one go about repressurising an EV - is it tricky?

 

[whistler]

Im not a qualified expert on this, but I had the same problem with a Chaffeteux boiler and in this case removing the boiler front cover revealed the expanson vessel which had a 'tyre' valve which was used to pump air into the vessel.

Of course you need to know the correct pressure. If your not sure its probably best to get an expert to check and re-pressurise. Shouldn't be too expensive.

 

[SYLVA]

At the latter stages of a Twelve Year lifespan, our Geminox condensing boiler’s expansion vessel had to be periodically re-pressurised by carefully using a car tyre foot pump, and the correct readings obtained using a digital pressure gauge. There are of course some necessary procedures to be followed prior to the use of a tyre pump. Eventually a replacement tyre valve and dust cap did the trick.
Ironically our replacement Vaillant ecoMax 622/2 condensing boiler installed in 2004 has recently developed a similar problem. I have checked for any obvious leaks, but found none, and the only anomaly I found , was a very large cold area on the downstairs lounge radiator suggesting an accumulation of sludge was present. I intend to check to see if the pressure relief valve is shedding water.
GH blackpool. I apologise if I appear to have intruded in your posting and burdened you with my own problems.

 

[GH blackpool]

GH blackpool. I apologise if I appear to have intruded in your posting and burdened you with my own problems.

not at all