[Sheks]

Hi,

Was wondering if there were any AV-Nut plumbers who frequent this place.

I am after some advice, the three port valve controlling our central heating as gone on the blink and won't power itself to heating any more. To heat the house I have to manually set the 3-port to the central position and put on the hot water to start the boiler / pump etc. This then heats the house (and of course the hot water).

I have done some research and it seems the 3-port we have whilst not particularly old is now obselete and not available. The updated version of the "control head" is not compatible with the valve body. So it looks like I need to have fitted a new complete 3 port control valve.

I am reasonably DIY capable, except for plumbing so do not feel confident / competent enough to do this myself. I am also afraid of being ripped off by a cowboy plumber.

I would like to pay a fair price for a good job.

Can any body give me a ball-park figure of what it should cost to supply and replace such an item.

Or would any plumber on here wish to give me a price (we are in Surrey, near junc 11 of the M25). We supply great coffee and donuts and I can "assist" (i.e. get in the way) and we can talk AV whilst we work.

Thanks in advance for any advice.

Sheks

[GaryB]

The most common problem with these valves is failure of the synchron motor. These are available for under a tenner if you're capable of fitting it yourself.

It's worth checking yours to see if that's the reason.

http://cgi.ebay.co.uk/Motorised-valv...QQcmdZViewItem

[Sheks]

Thanks for the tip GaryB

I am not sure it is this though, because it will power the valve over to hot water if I force it into heating.


Sheks

[GaryB]

Sounds like maybe the mid-position switch has failed. Depending on your skills, you may be able to replace it. There's some good info about how these valves work at:

http://www.gasheating.co.uk/Mid-Position-Valve.html

[Phil57]

Originally Posted by GaryB

Sounds like maybe the mid-position switch has failed. Depending on your skills, you may be able to replace it. There's some good info about how these valves work at:

http://www.gasheating.co.uk/Mid-Position-Valve.html

.........Does the water system need to be drained before replacing this switch?

[GaryB]

Originally Posted by Phil57

.........Does the water system need to be drained before replacing this switch?

No. It's part of the electrics. Make sure the power is turned off completely - not just at the timer/programmer before you start.

[RMCF]

Sorry to jump in and take this thread off on a tangent, but I too have a plumbing query that perhaps could be answered on here.

Sometimes when I have the heating on all day and there is a buildup of hot water, I get a banging/heavy knocking noise from my hot water tank in the hotpress. It might last for 10secs or so, but if you get it in the middle of the night if you leave the heating on it can scare the bejesus out of you.

This can be stopped if you move the thermostat round to a higher temp, but this then means I end up with water coming out of the taps that would lift your skin off.

Can I do anything to stop this?