We have a boiler downstairs and a hot water cylinder upstairs in the airing cupboard, and also 2 small round tanks higher up in the airing cupboard, one has the pressure gauge on it. Leak in the hot water cylinder (motor valve on the front). For reasons I won't go into as it will take forever I am tied to using one plumber who can't come til Thursday.
So as the water leaks out the pressure keeps dropping to zero and if I fill it up it just means more leak! So right now the pressure is at zero to avoid more leaking.
My question is does this mean no hot water as well as no central heating (all turned off atm to be on the safe side, can manage with no CH til Thursday but HW will be a pain)? I'm just not sure if the pressure thingy relates to the central heating only or not.
That is probably the worst description of a heating system ever but hopefully someone will know what I mean 
If anyone could advise I'd be ever so grateful!