Electric Shower Not Heating Water

m.j.w

Electric shower packed in today, not that much water coming out and its not heated at all. Probably need a new shower but just checking if there might be something fixable that it could be. I took the shower head of the hose and turned it on and its still not working so its not limescale build up in the shower head.

mazthespark

could try see if its gettin water and that the filter is clean. could be dirty and not letting enough water through or solenoid mite be stuck

Bruthal

What shower model is it?

If its a water flow problem, it could be the pump not running if shower is a pumped one, solenoid not working properly as said, filter blocked, although this seems rare enough once the shower has worked well after the initial installation.

Also attic tank running low for any reason could cause it. Heavily scaled heating tank in the shower unit also, but this would usually show other problems before badly reducing the water flow, but could still cause it.

It could also just need to be bled if the attic tank has run a bit low since the shower was last used.

2011

I would imagine that there is a safety interlock preventing the water from heating if there is low flow. Therefore I would think that if the flow problem is solved the heating issue will also be resolved.

As pointed out above this may be a blocked filter/pipe, airlock or a faulty pump.

Bruthal

2011 wrote: »

I would imagine that there is a safety interlock preventing the water from heating if there is low flow. Therefore I would think that if the flow problem is solved the heating issue will also be resolved.

As pointed out above this may be a blocked filter/pipe, airlock or a faulty pump.

Yes your right, the way it actually works on a pumped shower is, the start button on the shower simply starts the pump, and also energises the solenoid valve, and does nothing else. It is only a switch rated to a couple of amps at most.

The elements are supplied through the selector switch, and also a pressure switch and overheat cutout.

So when you press the start button, the solenoid valve opens, and the pump starts, which pumps water through the shower. This switches in the pressure switch which is what actually does the heavy switching on of the elements (according to how the selector switch is positioned). The exact same happens in mains fed electric showers except there is no pump.

So the above is how the heating is interlocked with the water flow. Sometimes when a shower is running, there is just enough flow to maintain a dynamic pressure to keep the pressure switch closed, but the water can still get far too hot, and this is where the overheat cutout comes in, particularly where there is enough flow to keep pressure switch closed, but limescale is insulating the elements from the water, and so the elements actually overheat, and operate the overheat cutout.

In this case the shower will cycle hot and cold because when the cutout operates, the elements cool down again, and so it cycles.


In the case here in this thread, its a water flow problem for reasons suggested in earlier posts. The make and model of the shower may help us give more ideas.

m.j.w

cheers for the replys lads, my tools are in work so wont be able open it up until tomorrow. It is a Mira ELITE 2 shower, would say its old enough. When I first noticed it the OH had just had a shower and it was working grand and then when I went in a few minutes later it there was a very low flow and the water that was coming out was not being heated at all. When I have it on the cold setting it sounds normal but there is a low flow and when I put it up higher you can hear the pump stuggling and there is hardly any flow then. Ill have a look at it tomorrow.

Bruthal

Seems like a definite water flow problem anyway. It wont heat once there is not enough water flow, due to pressure switch not being operated. This is to prevent dry or nearly dry elements coming on, or coming on with no flow of water.

The tank could well be scaled up. Lumps of scale can break off and then clog the heating tank in the shower itself. Could be filter as said previously. Faulty solenoid. Pump problem. Or the water supply has a problem, low level in attic tank. or it temporarilly went low and introduced air into shower supply. There are a few reasons which are easily checked out by someone experienced with them problems.