low water pressure

[chewy668]

have a worcesteer combi. water pressure keeps dropping. cant find any leaks on system. have to keep topping up water from refill loop

 

[John506]

Anything coming out the blow off? (copper pipe that goes through the wall at the boiler?)

Is your expansion vessel working properly, try re-charging it (search forum on how to)

 

[chewy668]

is the blowoff like the overflow

 

[John506]

Kind of, there is a valve in your boiler called a pressure relief valve, when the water heats up in your system it expands, and needs somewhere to go.

That's where your expansion vessel comes in, it takes up the expanded water. For it to work it needs to be charged (you can do it with a bike pump). If the vessel is nackerd or needs re-charging then the water has nowere to go, so it goes straight out your pressure relief valve.

 

[chewy668]

ok so how do i know if the vessel is knackered or needs recharging?

 

[John506]

Release all the air out of the expansion vessel via the valve, then attach a bike pump (with a pressure gauge) and pump up to the specification in the manufacturers instructions, or sometimes says on the top of the vessel.

Top your heating up if needed then turn on and see if it's done the trick.

 

[chewy668]

expansion vessell has water coming out not air. what does this mean?

 

[John506]

expansion vessell has water coming out not air. what does this mean?

Means the membrane inside the vessel has punctured.

Means new expansion vessel needed.

 

[chewy668]

that sounds expensive and like it could be a complicated repair

 

[John506]

Just get some quotes and go with cheapest all I can advise.

If you are planning to DIY then just do your research.

 

[chewy668]

ok, cheers