Low hot water pressure

[wanders1981]

Low hot water pressure

Hi everyone, I'm hoping someone is able to shed some light on my situation before I have to call out the professionals.

We've been in our house for over 3 years now, when we moved in the hot water pressure was pretty good (confirmed by a retired plumber family friend). Over time the pressure has got worse and worse and we're now at the point where by its getting bad.

We have a 200L hot water tank in the bedroom and this is fed from an expansion vessel in the roof. I checked the pressure yesterday and it was around 0.5 bar and I was not able to re pressurise it. I took the vessel off and to the local plumbing shop where they said it was dead. I purchased a new one and fitted it (no leaks) but the hot water pressure is still not any better. I checked the new unit too and it reads 3 bar (pre installed at that level).

I'm thinking it could be a build up of sediment as we live in a hard water area, does anyone know of anything else I can try before I call in the big guns?

 

[Ben-gee]

Just for clarity’s sake, did you change the red vessel or the white one?

 

[wanders1981]

Just for clarity’s sake, did you change the red vessel or the white one?

The white one, the red for the central heating has a filling loop

 

[Chuck]

Unless you are a G3-qualified plumber, you should not be making repairs to an unvented HW system. Your home insurance probably requires an annual check and no DIY repairs in its terms and conditions.

Has the system been inspected annually by a qualified person (normally the same on who services the boiler)? If not, get it serviced and, if it's the problem I have in mind, it'll be an easy fix for someone who knows what they are doing.

 

[Ben-gee]

The white one, the red for the central heating has a filling loop

I know that, thank you.
The reason I was asking is that I feared you were fiddling around with the unvented set-up which as Chuck explains above is not a good idea.

 

[wanders1981]

Thanks for the responses, I'll be on the phone to a professional tomorrow