Could British Gas Repair Have Caused This New Problem?

daveoc22

BG came yesterday to fix a problem under our service contract.

The water in the hot water tank was scalding hot. They diagnosed it as a faulty valve and fitted 'zone valve,inners,actuator and cylinder stat'. It seems to have sorted the problem.

However, in the evening we found that none of the downstairs radiators had any heat. The upstairs all worked.Maybe my imagination but they seemed too hot and the pipework and pump around the hot water tank were scalding to touch.

Any ideas of what the problem is with the downstairs radiators and is it likely to be linked to the BG visit yesterday. Seems too much of a coincidence for it not to be linked?.

BG are coming back tomorrow morning and I'd like to have some idea when they arrive.



Thanks

roger196

Assuming your system uses two port valves which look like www.screwfix.com part no 31480. You will have three of these which act like on/off switches. One turns on / off the water flow to the hot water tank, one for the upstairs radiators and one for the downstairs radiators. It looks like the downstairs one is faulty or the wiring was disturbed, most likely in the junction box ( part no 57815) when the work was done yesterday. Do not touch the wiring yourself as not only is it complicated but some installers have their own special version of what goes where.
The cylinder stat should be set to 60 degrees centigrade.
I would also check that the pump is working. If pump separate from boiler, hold pipes gently about ten inches from pump, turn on central heating and you will be able to feel flow. If pump within boiler, this can be done by holding the flow and return pipes about ten inches from where they leave the boiler.

daveoc22

Roger,

Thank you for your reply---problem is solved.

Would you believe that the British Gas man didn't turn the pump back on.

Turned it on and downstairs radiators warmed up immediately.

Dave

ormus

the 2/3 way port valves do not seperate downstairs and upstairs. they just seperate the domestic hot water and the CH system.

if you need zoned CH then you need 2 x 2 port valves. very rare.

1984ReturnsForReal_2

roger196 wrote: »

Assuming your system uses two port valves which look like www.screwfix.com part no 31480. You will have three of these which act like on/off switches.

3???????????

Please tell?

roger196

Honeywell Sundial S plan plus.

plumb1_2

roger196 wrote: »

Honeywell Sundial S plan plus.

Correct, but a rare install in most properties. Most are S or Y

Canucklehead

daveoc22 wrote: »

Roger,

Would you believe that the British Gas man didn't turn the pump back on.

Dave

HI

Puzzled. Pump and boiler are linked in J/B to fire together. Or pump live goes back to the boiler, for boiler with overrun.
Or did I miss something.


GSR

daveoc22

Canucklehead wrote: »

HI

Puzzled. Pump and boiler are linked in J/B to fire together. Or pump live goes back to the boiler, for boiler with overrun.
Or did I miss something.


GSR

Sorry but you've lost me there.

All I know is that the pump( 2 speed grundfos super 4), which is alongside the hot water tank, has on on/off rocker switch and he had left it off. When I turned it to on it immediately started pumping and the downstairs rads. warmed up within minutes.

It's a 30 year old system with a Concorde boiler. I've had it serviced every year and this was the first time I've had any sort of problem.

Canucklehead

Hi

As far as I know Grundfos (and other makes) do not have an on/off switch, only a speed control.
So, I would suspect that your pump doesn't have the strength to run your system on speed 1 but will on 2.
In the future if the same thing happens you will probably need a new pump.

GSR.

daveoc22

Canucklehead wrote: »

Hi

As far as I know Grundfos (and other makes) do not have an on/off switch, only a speed control.
So, I would suspect that your pump doesn't have the strength to run your system on speed 1 but will on 2.
In the future if the same thing happens you will probably need a new pump.

GSR.

Ah, I'm with you. So when I thought it was off it was in fact on speed one, which was not strong enough to pump down to ground floor.

Switching it to speed two( which is presumably what it is always supposed to be on) started things up again.

Still, the problem wouldn't have happened if the BG man had remembered to switch it back to speed two in the first place.

Thanks

Dave