Question about whether electric shower box or head affects temperature and pressure

[Soubriquet]

Stupid question about electric showers.

Is it the box or the head that controls temperature, and water pressure?

My shower has an annoying thing of starting out nicely, and then suddenly goes ice cold, and it takes forever to heat up again. This I’m putting down to the box.

If I wanted a better spray, or pressure, I’m assuming I need to look at the shower head?

How old is the existing unit and has it been heavily used? Do you get chalk in your kettle?

My guess is that the heating chamber is clogged up with chalk. Initially heats the water, low water flow so the thermal cut out opens and takes a long time to reset.

It’s the unit itself. Nothing to do the head.

I think my electric shower is 7.5. I would need to upgrade the electric cable to replace it with anything bigger. The shower is slow and lukewarm in winter when the water is so cold.

I need to make the leap and upgrade the cable and get something more decent put it. I am jealous of my friend's powerful MIRA shower.

My mother used her 20+ year old electric shower happily enough until it died after showing all the same symptoms. The replacement was magic, it was a shower, not a cold drizzle!

It’s about 3-4 years old. This is a HA house so it’s a basic generic thing

Sometimes ther is a filter in the connection from the shower body to the hose. Might be full of dirt. With the shower off, unscrew the shower hose from the unit and take a look, give it a poke with your finger, if there is a flter there take it out and give it a thorough clean, then put it back and screw the hose back on. Does your kettle chalk up?

Yes actuslly. We are in a hard water area.