Hot water Trickling out of Taps

inspectorperez

Just wondering if anyone can help?

Economy seven setup for water heating with an unvented water cylinder with expansion vessel sitting on top. Installation took place circa 1997 when apartments were constructed. Mains water pressure is fine with a flow rate of circa 35L per minute.

Over past few months the hot water flow has deteriorated to the extent that it is now just a mere drip.

Having googled the term "expansion vessel" I believe these have a finite life of about 15 years in general before things start to go wrong, e.g. internal membranes perish and need replacing or repressurising.

Would appreciate any observations from readers who have experienced similar or are familiar with this kind of setup.

I will try and add an image for context.

TIA

MattMattMattUK

One can often tell if an expansion vessel has failed by tapping it, if it sounds full at the opposite end to the inlet pipe then it has failed, if it is still hollow then it might not be working properly, but it it probably has not failed. They also normally need the pressure checking and adjusting once every year, so it might not have failed, it might need adjusting.

The think on the right of the image, with a gap in the middle of the pipe section, that is a tundish, is it wet in the middle?

That being said the expansion vessel will have nothing to do with water flow through the taps, that is most likely some kind of blockage, if you live in a hard water area it is probably limescale clogging the outflow pipe.

inspectorperez

https://forums.moneysavingexpert.com/discussion/comment/81924853#Comment_81924853

Thanks for that Matt.

Not at property for next few days but will check out at next visit. It is incidentally in a soft water area.

Am I right in saying that there will probably be a schrader valve somewhere on the expansion tank to enable the pressure to be checked and topped up if necessary?

MattMattMattUK

There should be yes, you will probably find it is under the black plastic cap at the top of the expansion vessel.

inspectorperez

Just to complete this thread if anyone experiences a similar issue in future, a new expansion tank and combi valve have solved the problem. On examining the old combi valve, it was caked in limescale and the filter was completely choked. It was a non maintenance item so am not

aware of what could have been done to prevent the issue, but everything working fine now.

QrizB

I'm glad you got to the bottom of it!