Water runs out too soon - advice needed...

July1962

Please bear with me – I know nothing about plumbing but will try to explain my problem…

I have a big cold water tank in my loft. Below the loft is the airing cupboard with another water tank (immersion heater?) It has an insulating jacket on.

Several months ago my radiators failed to heat up. A friend of a friend recommended a heating engineer, who came out and replaced a small metal box in my airing cupboard (heating pump?)

Before he left he said he needed to check the water levels in my tank in the loft. He went up and did something – not sure what. He said something about if the level was too high I’d be flooded.

Ever since his visit, I haven’t been able to get the bath to fill up more than ¾ before both hot & cold taps run dry. Also, the sink taps won’t work for ages after my bath.
(A few hours later the taps are back to normal).

I’ve put up with it because I was reluctant to call the chap back in case he was one of those cowboys I’ve seen on tv (deliberately doing stuff to your home to ensure you call them back – then charge you for it).

I also didn’t have the cash to call out another plumber to try to fix it.

Can anyone tell me if this is just a simple thing I can do myself (ie: turn something anti-clockwise for half a turn) or should I seek the help of a professional? Whatever he did, it was done in the loft (where the cold water tank is).

Any advice gratefully received.

Cardew

You have a pretty standard system.

The cold water tank in the loft should fill to a set level every time you use water(hot or cold). That level is set by a ballcock mechanism - much like you get in a toilet cistern.

The 'ball' floats on the water. When the water level drops, the ball drops and opens a valve that lets in water from the mains. It sounds like this mechanism is not working and only allowing a trickle of water into the cold water tank. Normally the problem is the opposite - the ballcock doesn't shut off the water properly.

If you have access to the cold water tank, push down the ball and water should come through at quite a rate. If it doesn't look for a tap that the plumber might have turned off.

If it is any consolation it doesn't sound like a serious problem and replacement of the ballcock(if required) is not expensive.

macman

But why do both hot and cold taps run dry at the same time? A sticking ballcock would not explain whay the hot feed fails as well.
And the OP says that after this there's no 'sink' supply for a time. Assuming that they mean the kitchen sink, that is fed off the rising main, so a fault in the cold tank should not interrupt that supply.
I think the 'small metal box' is not the pump, but a motorised valve that was replaced?
OP, how are you heating your water-using the immersion heater, or hot water via your gas boiler?

Premier_2

macman wrote: »

But why do both hot and cold taps run dry at the same time? A sticking ballcock would not explain whay the hot feed fails as well.
And the OP says that after this there's no 'sink' supply for a time. Assuming that they mean the kitchen sink, that is fed off the rising main, so a fault in the cold tank should not interrupt that supply.
I think the 'small metal box' is not the pump, but a motorised valve that was replaced?
OP, how are you heating your water-using the immersion heater, or hot water via your gas boiler?

You are correct that this shouldn't affect the cold tap in the kitchen that will be fed direct from the mains.

However, I think the OP was referring to the wash basin in the bathroom when they mentioned the sink.

It could well be that both hot & cold water is supplied to the bathroom from the storage tank, and it appears the storage tank is not refilling quick enough to counter the draw from the taps.

(The storage tank is usually quite big, so if it only fills 3/4 of the bath, it sounds like the ball valve maybe set far too low)

macman

But the hot supply must be from the immersion heater tank. Why do both fail at or around the same time?
I think we need more info from the OP.

July1962

Thank you for all these replies!!

I was referring to the bathroom sink taps. When the bath taps run dry, the sink taps are also dry.

My water is heated by the immersion heater in the airing cupboard (there's a gas boiler on the kitchen wall).

The original woe was non-functioning central heating, which the chap fixed by replacing a small box which he referred to as a pump. (Heating now works).

Thanks again for all your messages

peachyprice

macman wrote: »

But the hot supply must be from the immersion heater tank. Why do both fail at or around the same time?
I think we need more info from the OP.

Because the hot water tank is filling from the cold water tank, not the mains.

It sounds as if the 'plumber' has partially closed the stopcock into the cold water tank so it's not filling as fast as it's emptying.

OP do as Cardew suggest, go into the loft and see if the ballcock is working properly and that the stopcock from the mains supply into the tank is fully open.

July1962

Thank you

I'm recovering from a medical procedure, but will go into the loft as soon as physically possible and see if I can suss out whether the ballcock is stuck / too low down.

I had no idea the water tank worked the same way as my toilets!

You guys are a mine of information

macman

Why not ask the plumber to come back and correct the fault, since it's evidently something that resulted from his trip to the loft?

July1962

I was a little worried that he was a 'cowboy' and had interfered with the flow on purpose, so I'd call him out with another problem further down the line. I'm therefore a tiny bit reluctant to let him near my pipes again, however, if I can't fix it myself I may well have to

macman

He seems to have fixed your CH pump without finding other 'faults' to fix and charge for there and then. He could have told you that you needed a new boiler, so maybe you ought to give him the chance to rectify his possible error. At least call him up and describe the problem and see what he says.