cold water tank overflowing with lukewarm water

[Kikii]

Good afternoon

This is my first email to your forum. I don't know anything about central heating so please use simple words. Thanks for the forum. I've been having a problem with my overflow tank for sometime now. It started when we had one of our hot water taps changed (pillar tap). Since then water has flowed continuously from the overhead tank. The ball valve has just been changed, pump, thermostat also changed but problem stll remains.
We do get central heating but water never really gets hot. We leave the cold water tap in the bathroom open and this stops the overflow. The water from the cold water tap is also lukewarm.



The pipe leading to the hotwater tank on top of the tank is always ice cold. It never used to be like that. Used to warm up when the hot water was turned on. All other pipes leading to/from hot water tank which are supposed to be hot are very hot. We've had 5 british gas engineers come over who've done the above jobs and have recommended power flush.

We've had a plumber sent from british gas also come over because they thought it was plumbing issue but the plumber reckoned it was the thermostat which needed changing and/or pump which have both been changed. The plumber said the powerflush is to do with the radiators and if those are working then that is not the issue. Can you please help as we're very confused with what's going on.

This is the large cold water tank.

Many thanks. Kikii

 

[stevetheplumber]

Good afternoon

This is my first email to your forum. I don't know anything about central heating so please use simple words. Thanks for the forum. I've been having a problem with my overflow tank for sometime now. It started when we had one of our hot water taps changed (pillar tap). Since then water has flowed continuously from the overhead tank. The ball valve has just been changed, pump, thermostat also changed but problem stll remains.
We do get central heating but water never really gets hot. We leave the cold water tap in the bathroom open and this stops the overflow. The water from the cold water tap is also lukewarm.



The pipe leading to the hotwater tank on top of the tank is always ice cold. It never used to be like that. Used to warm up when the hot water was turned on. All other pipes leading to/from hot water tank which are supposed to be hot are very hot. We've had 5 british gas engineers come over who've done the above jobs and have recommended power flush.

We've had a plumber sent from british gas also come over because they thought it was plumbing issue but the plumber reckoned it was the thermostat which needed changing and/or pump which have both been changed. The plumber said the powerflush is to do with the radiators and if those are working then that is not the issue. Can you please help as we're very confused with what's going on.

This is the large cold water tank.

Many thanks. Kikii

process of elimination turn of the heating and hot water shut all the valves except the main and see if it still overflows if no then turn on each valve in turn see if that starts it you can even look in the tank as each one is turned on to see if you can see movement of water back filling the tank
if its still ok heating then hot water can be tried in turn

 

[Kikii]

thanks, I'll try that and let you know the outcome

 

[Winston]

Keep us posted really good bunch of people here to try and help out