Plumbing Question - Shower not hot

[Mark Wright]

I've rewired the cable to the immersion heater and ill do a continuity test on the element.

 

[brianmoooore]

The immersion heater would normally be switched off. It's only there to a) block up the big hole in the cylinder, and b) as an emergency backup if the boiler is out of order.
The problem with the shower is definitely the non working of the shower pump. Everything that has been discussed before is now irrelevant.
Do you have a non contact voltage detector (Volt Stick)? If so, wave it around the pump cable to see if it is live.

 

[mainline]

The immersion heater would normally be switched off. It's only there to a) block up the big hole in the cylinder, and b) as an emergency backup if the boiler is out of order.
The problem with the shower is definitely the non working of the shower pump. Everything that has been discussed before is now irrelevant.
Do you have a non contact voltage detector (Volt Stick)? If so, wave it around the pump cable to see if it is live.

The OP said that the pump comes on with the shower #66

 

[brianmoooore]

Ah, so that's what that short video was about. Doesn't come over very well on a laptop without sound. Listened to it on my phone now, and it doesn't sound very happy, but having been asked many times to diagnose car faults from videos, I know that's the norm.
The black connectors at the top of the pump flexible pipes often have quarter turn isolator valves built into them. If they are present, are they all fully on?
I've also come across pumps where there are little mesh filters built into the rubber washers between the nuts at the bottom of the flexible pipes and the pump.
All comments about the shower valve having a to high minimum pressure requirement are now invalid. Something's blocking the hot water flow.

 

[brianmoooore]

The connection at the top of the cylinder is known as a Sussex flange. Google it to see how it works.

 

[Mark Wright]

Thank you sir ill invvestigate.

 

[Mark Wright]

I'll just say with the with the immersion heater on it's too hot - on max its like boiling hot - its dangerously hot. I've switched it off for now.

 

[brianmoooore]

I'll just say with the with the immersion heater on it's too hot - on max its like boiling hot - its dangerously hot.

Is that from the shower head? With the temp. knob against the safety stop or overridden?

 

[mainline]

The connection at the top of the cylinder is known as a Sussex flange. Google it to see how it works.

Surrey and Warix flanges are top entry.
Essex flange is a side entry.

 

[Mark Wright]

Is that from the shower head? With the temp. knob against the safety stop or overridden?

Both - Remember I changed the calibration to be the total max. Now with the immersion on it's too hot -Dangerous.