Electric Water Heater - Noisey

[Diane]

I have a water tank that is heated overnight. It is extremely noisy and it sounds like a boiling kettle(only much lounder!!) after it has been going for about an hour. The water is extremely hot (only of late) and I have howling noise when I run cold water. It all seems to have happened since I had a new kitchen installed and the system had to be drained to change the pipes for the kitchen and the washing machine. Can anyone give me a little advice before I send for the Plumber so that I know they aren't talking gibberish? I have absolutely no idea about plumbing at all and don't want to pay a fortune for things done that wouldn't be necessary. I have heard so many horror stories about people being ripped off in the past.

[Today's]

Hi Diane

Can't diagnose your problem properly without more info or looking at the system but suspect either the thermostat is not working or been dislodged and maybe you have an air lock in the system. How is the water heated? do you have a boiler or just an emersion tank.

If you need to get someone out, make sure they are "corgi reg" and that you check they are, this will cut out most of the cowboys.

[Diane]

Thanks for the response. It's a large(what looks like hard foam) jacket tank. I'm not sure what it is called but it has two ways of heating water (overnight -which is the problem and by pressing a switch in the kitchen). There is a cold water tank in the attic to feed it. Recently I had to have the "float" changed in the attic as there was hot water pouring onto it and it melted leaving me with warm water flowing out of the overflow pipe into the garden. Aren't Corgi people for Gas only?

[Maudlettice]

It sounds like your immersion heater has given up the ghost. Look around your tank and either near the floor or at the top (there are various types) you should see a plastic thing projecting with an electricity wire connected. Examine the plastic thing to see whether there is a ring that can be turned with numbers on it, if so this is the dial which sets the water temperature. Turn the dial to its lowest temperature (lowest number) and see if this stops the boiling up. If it does, then it is only a question of turning the dial back up until you reach a temperature which you are comfortable with, and thats it. If the boiling continues whilst at the lowest setting, then a new immersion heater is necessary. It means draining down again to below the tank (to save costs you could do this yourself before the plumber arrives rather than pay for a man standing around whilst the taps empty - remember to go to the feeder tank and tie up the ball-valve) and a plumber with a large spanner for immersion heaters to take out the old and put in the new. There are different sizes of immersion heater (lengths) and different types depending whether it is at the top or the bottom. However, a chat by phone with your local Plumb Centre might identify it and enable you to buy it direct rather than through a plumber. Corgi is for gas fitters, not plumbers. Ball park - expect to pay around �30 for a new heater and maximum 1 hour for a plumber if you drain down first. Hope it is only the thermostat that needs re-setting - let us know if you can. Best wishes.

[Maudlettice]

I should have included that when you examine the plastic thing if the thermostat control is not immediately visible it may be under a plastic cap which you will have to remove by undoing a couple of small screws (switch off the electrity first - follow the wire back there should be a switch on the wall). Also, around here it is usual to pay �50 - �80 (depending on your luck) for a plumber for an hour including all tools and jointing materials.

[Diane]

Thanks for the responses. It turned out to be the "rod" that controls the temperature that heats the water from the bottom of the tank. It took all of five minutes to replace and I found a really nice Plumber who did it for me. Peace is now present in the house at night.

[Vasquoy]

I have the same problem with my tank, with the water definitely boiling. I have it on Economy 7 and I have to have the water on for the heating to work as well. However, a few months back stuff started coming out of the hot water tap which was like a blue/cyan "chalk" with a brown tint on one side. It broke up easily when rubbed between your fingers - and for some reason the thermostat appears to be kicking in again. I take it this is some kind of limescale???? And why when this has kicked out is it working?? Last question, if I do need to replace the rod as Diane had to do, how easy would it be to do myself???