Electric shower only produces scolding hot or ice cold in hotter months. Any idea what I can do to fix this or is this normal?

[endecotp]

I will admit am sensitive to heat

Right....

Get a thermometer that you can use to measure the water temperature.

 

[Alec_t]

I'll give it a few quarter turns. Its currently turned to 12-6 position with the pipe running vertically. ill give it a few turns

If it's the usual isolator/service valve then it's a quarter-turn type. The 12-6 position is fully open (and the 3-9 position is fully closed).

 

[jj4091]

It still seems like the problem is the flow rate either into or out of the shower unit. See these instructions about flow rate and maintenance.
https://www.bristan.com/product-files/576763/fitting-instructions.pdf perhaps you just need to clean both filters

If you can achieve the required input flow rate but not out then it would suggest that the stabiliser valve is is either blocked or faulty

Google Search

 

[Johntheo5]

Eco power setting on most showers is generally ~ 60% of full power so yours certainly shouldn't be greater than say 5.0kW. At a present mains temp of 17C it only requires a flowrate of 3.12LPM to have a comfortable 40C shower, if it's just about reaching its cut out temperature of 50C, but isn't, then the flowrate can only be 2.17LPM or less. A healthy shower should flow between ~ 2.0 and 8.0LPM MIN/MAX temp control settings.

 

[endecotp]

It still seems like the problem is the flow rate either into or out of the shower unit.

Why do you say that? He has measured the flow rate and it seems reasonable to me.

 

[HERTS P&D]

Faulty electric shower,........................................... just replace it.

Andy

 

[jj4091]

Why do you say that? He has measured the flow rate and it seems reasonable to me.

He only meausured 1 litre of water a couple of times. I don't think that is enough to rule out whether it varies or not. According to the instructions there are 2 elements in the tank for high and low and the temp is varied for each element by the flow rate which is cintrolled by the stabiliser valve unless I am misunderstanding. So he really needs to rule out all other possibilities ie filters and limescale before he invests money in the more expensive part.

 

[Diver Fred]

I am comfortable with looking under the cover but not entirely sure what I'd be looking for. Am i looking for damaged wires/loose wires from the mains to the unit?

You need to check that the 2 heating elements are not linked together on both sides of the elements.
Switch the mains off before taking the cover off.
With the hot/eco/cold switch in the cold position check, at the switch, with a meter - on resistance setting - that the two live 'sides' of the elements are not short circuit. you will see a small reading but not a less than 2 ohm reading. Also check
If that is OK switch to 'Eco' and repeat the resistance reading. That should be similar values.
Finally repeat with the switch in the 'Hot' position, the meter should now indicate a short circuit.
If you see a short circuit in both the Eco & Hot switch positions then that is indicative that the switch is faulty.
Switch the mains off before taking the cover off.