have 2 tanks in loft 1 small one large however i still believe its mains fed as when i turn the water off at stop cock under sink in kitchen the water goes off to all the cold water toilet shower sink tap and bath tap I also thought it should be like that but seems that it is tank in loft is full of water but just seems to fill hot water tank in the airing cupboard

steve, July 2009

I suffered poor water flow upstairs - both hot and cold would almost dry up particularly in the morning after a bath had been run.

The feed pipe had collected brick dust and other small debris, restricting the inlet flow and the draw-off was eventually defeating the flow rate into the tank - after a bath had been run the outflow was dependent on the poor flow into the header tank.

My solution was to fit dual inlet valves to the header tank, each with its own ball float and to put a filter into the rising main with a stop valve immediately above and below - so the filter could be removed and cleaned.

No problems after that.

Peccavi, July 2009

The small tank is the heating system flow and expansion tank - about 4 gallons capacity.
The large one is the cold water header tank (40 galls or more) and this keeps your copper cylinder topped up, and this is where the water is heated from your boiler. This tank may also serve a gravity shower with cold if you have one. This tank is kept topped up by mains cold water. All of your hot taps are fed from the copper cylinder, via the outlet right on top. The cold taps in your house are fed directly from the water main which is why they shut off when you close the stopcock.

John, July 2009