Water Slow to Heat and Poor Pressure - Two Switches in Immersion Heater Cupboard

[terryplumb]

Your shower isn't faulty. The dial at the top controls how many heating elements are in use. The lower dial controls the rate of flow that water runs thru the shower. On the basis that the faster the water passes thru,the less time it has for heat to transfer. So turning lower dial clockwise reduces the flow ,and water temperature is hotter ( and vice versa)
On the setting you have top dial ,all heating elements are in use and minor adjustment to heat is controlled by the lower dial by altering the flow.
Electric showers are never brilliant ,and you shouldn't expect much more than 3 or 4 litres per minute of water to flow at a reasonably hot temperature. And probably less than that in winter ,when the cold water temperature delivered to premises is lower.

 

[JohnD]

It's not faulty, it's just that UK electric showers are rubbish. They don't draw enough electricity to heat a reasonable flow of water to a reasonable temperature. You can usually get one or the other, but not both. It will be worse in winter.

Edit

Too slow to read the new page.