Cold water tank in the attic overflowing

[GGg]

Turned mains water back and and immediately started going back up into the tank. I can’t access shower mixer to isolate but assumed isolating the entire feed off the hot water pump would do it.

 

[Riley]

So it literally feeds the pump?

 

[Riley]

Sorry I’m getting mixed messages with this does the pump do hot and cold water for the whole house or just for one shower. If all the house is pumped then the fault can only be with your kitchen mixer

 

[GGg]

Sorry I’m getting mixed messages with this does the pump do hot and cold water for the whole house or just for one shower

Pump does whole house, hence I thought if I used the isolation valves on the pump it would stop any backfilling mains. But either the isolation valves aren’t turning off fully or im barking up the wrong tree. However I can feel the pipes on the pump they are cold as if mains water is flowing through.

 

[Riley]

Kitchen mixer won’t be pumped

 

[GGg]

Kitchen mixer won’t be pumped

Kitchen mixer is pumped, turns pump on etc.

 

[Riley]

Only on hot, the cold should be straight from the mains

 

[GGg]

Only on hot, the cold should be straight from the mains

Yes. 3 taps and shower are all like that.

 

[GGg]

Only the bath is tank fed hot and cold.

 

[Riley]

Right let’s backtrack as we keep going round in circles here. Any outlet you have that is hot pumped and cold mains could be your culprit and from what you said sounds the only logical explanation