Hello - am hoping someone out there can offer some advice...
I've been living in a split level 1st & 2nd floor masionette for two months, which was built in the 60's.
Heating is provided via combi boiler. Water for kichen is fed straight from the mains supply (both hot and cold), however, we have separate bathroom and WC upstairs with setup as follows:
Hot water (bath and sink) is fed via mains/combi - water pressure is excellent.
Cold water (bath, sink and toilet) is fed by a cold water tank in an elevated water tank cupboard/loft space in the bathroom - water pressure is poor.
Our toilet takes over 8minutes to fill. The water pressue in the bathroom sink is poor.
The strange thing about the bath (which is a mixer tap with shower head hose connected) is that the pressure via the cold and hot water taps (when running just a bath) is almost identical, and I can balance the hot vs cold nicely for desired temperature. However, when you run the shower the water pressure is great if solely running the hot tap (as you would expect as its fed off of the mains water supply), but as soon as I dial in some cold, the water pressure is so poor I simply don't use cold water anymore whilst running a shower. So I am basically reliant upon the hot water temperature set on my combi boiler to act as the max temperature for my shower hose.
I don't know enough about bath mixer taps, but it just seems odd that the water pressure for both hot and cold on the main bath taps is fine. But as soon as you activate the shower... the cold water is pretty much unsuable.
I know the immediate solution would be to simply connect all my cold water supply to the mains. But this still doesn't explain why the water pressure for my shower is so poor the moment the cold water tap is turned on. I understand gravity, elevation etc, but then wouldn't the bath cold tap have poor water pressure too, as that is still getting the water from the tank above?
Does anyone have any ideas? Any help would be greatly appreciated