Expansion Vessel on hot water system

[TamHam]

I am currently experiencing problems with the temperature of my hot water. At first I thought the mixing valve coming from the thermal store was broken, however, when I went to pressurise the vessel, water was leaking from the vessel valve.

My question is, would a faulty expansion vessel effect the temperature of the water? Ie colder than it should be.

 

[ianmcd]

is it a thermal store ? or is it an unvented HW cylinder, they are not the same, make and model or some pics what you have will get you the correct advice

 

[TamHam]

It's an Albion Mainsflow indirect system, which has a thermal store.

The water going into the blending valve is hot however the water leaving the valve is lukewarm.

 

[Agile]

I don't see any way the EXV on the hot water outlet could affect the blended hot water output.

Those valves tend to get gunged or scaled up after a few years. In most cases they can be cleaned with acid but it is messy and easier replaced as they are not so expensive.

Tony

 

[Alec_t]

I don't see any way the EXV on the hot water outlet could affect the blended hot water output.

I'm no plumber, so tell me if I'm wrong, but is it possible (depending on the construction of the mixer valve) that loss of air from the EXV would allow pressure build-up in the pipework if all H and C taps are closed, thereby applying excessive pressure to the valve and (perhaps with the assistance of any crud present) jamming it in the wrong position?

 

[PullerGas]

Oh its a Sludge Bucket!! They're generally just a wee 'shock absorber' type vessel. Wouldn't effect the water temperature.