Hot Water Tank Overflow Has Water Coming Out

[lankeela]

I have an immersion heater that I kept on all the time. The last time I ran a bath a few days ago the bathroom seemed to fill up with steam - I didn't think anything of it other than maybe it was because I hadn't run much hot water off. The other morning when I came home from work there was water gushing out of the overflow pipe into the garden. Spoke to a colleague who said it was either the hot water overheating or the ballcock sticking or needed replacement. I have been running the hot tap just a little to stop it overflowing (been at work most of the time since then) but when I turn the tap off it overflows again after a short while. As I turned the immersion off as soon as this happened I presume it isn't down to it overheating and must be the ballcock. Is it a big job - I have never been in the loft and don't think I could reach to get up there anyway! Any ideas?

[bhg481]

It shouldn't be a big job. Possibly just adjustment needed but a new valve assembly is less than a tenner and not difficult to fit.

[Mick-the-Miller]

It could be just a bit of limescale stopping it moving freely - you won't find out if you don't have a look.

Have you got a ladder or can you borrow one from a neighbour?

The other path is to get a plumber in!

[The Builder]

The first thing I would go for is the thermostat in the immersion cylinder, Lanky.

It does sound as though the immersion is overheating and sending hot water and steam up the expansion pipe and into the roof tank. As the roof tank overfills, the excess shoots out of the overflow and into the garden.

Very quick and simple DIY job. Just make sure you get the right length thermostat. Best way is to remove the old one first and measure it.

[lankeela]

Thanks all, bit confused though because I have turned off the immersion and there is only cold water now flowing through the pipe/tank and out of the overflow if I turn the tap off - why would this be if its the thermostat if there is no hot water being heated? Sorry to be thick!

[Sipowicz]

Sounds like the ballcock then.

[bhg481]

It sounds more like the valve assembly. If you can get up there start by pushing the ball down into the water to make run in at full rate - it will run out of the overflow. With any luck, if there is something stopping the valve closing properly that might clear it.
If that fails try adjusting the float - it's usually just a nut adjustment on the end.
If that doesn't work you may need to replace the valve assembly. As I said in my first post it's not an expensive part and shouldn't take a long time.
If you have hard water and no water softener it could be that the sealing washer in the valve has got limescale on it which could stop it making a good seal.

[BRIGHT SPARK]

Lanky...it sounds like the ball valve in the cold water tank.As said its an easy fix...go for it!

[Old_Geezer]

"don't think I could reach to get up there"

That's what loft ladders are for ;-)

If the loft is floorboarded at least you don't have to step from rafter to rafter.

It should be easy to bend the bar with the ball on so it stops filling before the wtaer level reaches the overflow. Shouldn't be that expensive to get it fixed properly if you get some in to do it, either.

[lankeela]

Ok will give it a go - I might be gone some time!

[The Builder]

I'll be interested to see how you get on, Lanky. Perhaps the excess hot water and steam may just be a coincidence.

If it's the float valve, you just want one of these.........

http://www.screwfix.com/p/part-1-float-valve-brass/23847

It may simply be that the water level in the tank is set too high. Before replacing the valve, just bend the arm down a bit, drain off some ater, and see what the level is. Aim for around 2" below the overflow outlet.

[ivor4781]

we had this once.the immersion heater thermostat had stuck and was continually boiling the water (this was before the new regulations came out with the cut offs now standard)

[PeteHull]

Call a Plumber....