know anything about taps and plumbing?
We have boiler in kitchen,large tank in airing cupboard fed by small tank in loft. Do I have to stop feed in loft and and empty hot water system before I can fix tap. Or is there normally a stopcock in airing cupboard, there are some gate valves but not sure what dose what .Difficult question I know when you cannot see system
any info appreciated
Answers:
Well....first, shut your boiler down, just to be sure. To save aggro with gate valves (these are notorious for 'passing' anyway) shut off the tank feeds by pulling the ball valves closed with a bit of strong string. Now, open your COLD tap, this should empty the cold tank, which feeds the hot. When the cold stops, then open the hot, very little water will come out, you should still have a hot tank full of hot water. Now, remove the hot tap top, strip the tap. I have frequently seen a tap washer parted company with the tap, causing this grief. The others who answer in terms of scale and rusting blocking the pipework however are also perfectly correct. If you are in UK, plastic piping eg HEP20 is perfectly good, in fact can be used within 2 ft of a gas boiler.
Other answers:
there should be a valve in airing cupboard .turn off for hot and drain excess in pipes .
there should be a valve in airing cupboard .turn off for hot and drain excess in pipes .
Normally you have a gate valve or shut off valve before the boiler. The water from the boiler is usually taken from the top of the tank(inside the tank) It sounds to me like you need eithe a bigger tank in the loft or 2 seperate taks...one to feed the cold water and one to feed the hot water system. That way the pressure will not drop when you turn on both taps.
Sounds to me like you have some lime build up, or mineral deposits on some of your valves, for the hot water to run slow...
Find your shut off valves, and work them a few times, to see if you can get the "minerals" loose from them, (sometimes they build up in the "gate" if it hasn't been "worked" for a long time).
Or, you may have 'galvanized pipes' (the grey ones that look like steel), and they are rusted inside, or corroded with mineral deposits and will need to be replaced with copper or pvc pipe. (I would go with pvc if your plumbing code will permit it, because its so much easier to work with, and less hassles, unless you have "pex" available, and can find some one who knows how to clamp the fittings, as its the easiest one to use entirely).
I wish you well..
Jesse
Johncob seems to know what he is talking about. I would like to add my threepence worth. I have seen houses plumbed in half inch pipe instead of three quarter pipe. The only solution is to have them re-plumbed in 22m.m. pipe, this DOUBLES the flow. Its not a bad idea increasing the height of the tant in the roofspace. In an old house there is usually 1 or 2 old tanks rusted through. Put the new tank on top of an old tank it makes a difference to the pressure.