overflow problem

[tilex]

Hello there i'll try to keep this as brief and simple as possible i've just fitted a 50 gallon tank in the roofspace above my bathroom to supply a 2 bar shower pump, this tank only supplies the pump cold, it is mains fed and has a ball valve.The hot water cylinder and pump are on the same level as the bathroom. The original cold tank that supplies the h w cylinder etc is located in the top roof space, which is a loft conversion with bathroom, along with the f&e tank. The tank is virtually inaccessible and too small to supply a pump hence the reason for installing a separate tank in the roof space below. Ok if your still awake the problem is the new c w tank is overflowing (not the ball valve) and the ball valve is submerged, i suspect the original tank upstairs is backfilling my new tank via the pump cold feed in an effort to find its level, the only solution i can think of to this problem is a single check valve on the cold feed to the pump to prevent t it back filling very unusual i know but can anybody see any problems with this any input would be appreciated CHEERS

 

[seco services]

no good having two tanks on different levels
and don't fit a check valve between the supply to pump as the pump mi will say the pump needs to vent.
why don't you feed the cylinder from the same tank as the pump ?

 

[bengasman]

you need to keep the 2 tanks completely seperate

 

[tilex]

you need to keep the 2 tanks completely seperate

SORRY WHAT DO YOU MEAN THE TANKS ARE COMPLETELY SEPARATE

 

[seco services]

supplys for pump need to be from same tank.

 

[bengasman]

the new c w tank is overflowing (not the ball valve) and the ball valve is submerged, i suspect the original tank upstairs is backfilling my new tank via the pump cold feed

in which case they are not completely seperate