DIY Doctor UK DIY Forums

I live in a flat and have no access to the water tank(s) in the roof.

How can I tell if the cold water in my flat is fed
a) directly from the mains or
b) from a cold water tank in the roof

I am about to install a shower pump and am not allowed to fit a pump to the mains.

So I need to verify where my cold water is coming from.

How can I tell ?

I would guess the whole flat is mains fed.

Drinking water has to be mains fed, The water regulations state this.

If you have no access to any tanks, the whole flat will be mains fed.

The easiest way to tell is to try to follow the pipe from the mains stop tap to see if it feeds the bathroom.

Chances are that its mains. You need mains for your drinking water so the kitchen tap should be mains. Turn off you main stoptap and run the bathroom cold supply. If it is dead, then you bathroom is mains. Bear in mind that your hot could also be mains unvented. This will run for quite a while as the expansion vessel empties with the mains turned off. Another way would be to measure the temperature of the kitchen supply and the bathroom supply. Run both supplies for a couple of minutes and then see if there is a temperature difference. This is not conclusive but a guide. A tank fed supply will be slightly warmer than mains depending on usage. You could also try measuring pressure. Tank fed being lower than mains unless your tank is very high. Good luck.