Should my water heater switch be on constantly?

[britishboy7]

Recently moved into an old 1930's semi with copper cylinder in the airing cupboard and water tanks in the loft (my old flat had a combi boiler = nothing to understand, immediate hot water on tap)

Had a fair bit of work done indoors recently including a powerflush as the sludge knackered our CH pump, and a surrey flange fitted to the copper cylinder. Looked in the airing cupboard and the fused switch inside that says 'water heater' was on. I switched it off as I thought it was a type of override feature? Anyway, with it switched off yesterday, no hot water this morning, is this normal?

Please help

 

[Burnerman]

The water heater switch controls an immersion heater, fixed into the top of the copper cylinder. maybe this is your only source of hot water?
John

 

[britishboy7]

Thanks John, I'm sure the Mrs or me switched it on a few weeks ago as had 3 people wanting a shower one after another before a night out, as we thought it would warm the water that refilled the cylinder quicker?

We had the oil boiler served by GB a couple of months ago and he said it was fine (he replaced knackered CH pump at same time) and the 3 way switch was replaced a couple of months prior to that (that switches hot water to taps and to radiators)

Is it normal for the immersion to be on constantly? I'm sure it never used to be

 

[Burnerman]

The immersion heater has its own built in thermostat usually set to 60 deg.....so if your boiler keeps the tank at that temperature, the immersion is off anyway.
Personally I use my own oil boiler to keep the copper cylinder hot, but I boost things with the immersion as necessary......oil is much cheaper than electricity, especially just now! (27p per litre, 1000 litre drop )
I'd just switch the thing off until its needed - but I'm surprised to hear that you had no hot water.....unless the boiler was switched off too, of course!
John

 

[JohnD]

you mention the cylinder is copper. If this means it does not have a stiff foam coating, it will lose quite a lot of heat. You can insulate with one, or better, two, red jackets, and also lag the hot pipes around it. An insulated cylinder will stay hot for about 24 hours, or until used up.

Electricity is an expensive way to heat the HW, but very useful in case your boiler is out of action. It will be more economical to leave the immersion heater switched off if the boiler is working. An immersion heater costs about 30p per hour, until it reaches the temperature on its thermostat, and will warm about a litre of water per minute.

If you find the cylinder is cooling quickly, there are some plumbing faults that can cause it.

 

[D_Hailsham]

the 3 way switch was replaced a couple of months prior to that (that switches hot water to taps and to radiators)

You seem to be confused. Firstly, the '3 way switch' is a mid-position motorized valve. This directs the water heated by the boiler to the rads or the HW cylinder or both. Secondly, the water circulating through the boiler is not the same as the water coming out of the taps.

Your hot water cylinder should have four pipes connected:

bottom - cold water inlet for cold water tank in loft
top - hot water outlet to taps
side (two connections) inlet and outlet for the heating coil in the cylinder. The boiler water passes through the coil and heats up the water in the cylinder. The top connection should be joined to port B of the mid-position valve.

If the hot water is not heating up, the mid-position valve could be faulty.

What are the settings on your timer?