Could 4 bar static pressure prevent shower off combi getting hot enough?

[WaterTight]

Or rather it gets hot enough but only when turned to almost full hot or higher. With the taps if you turn them on a little it's very hot, turn them on full and it's almost cold.

Would a PRV be first thing to try? Or could it be something wrong with boiler?

Shower is new so not cartridge adding to issue.

Thanks

 

[chris watkins]

Water Flow Control Products by Aquaflow Regulators Ltd

It is most likely that you need to reduce the flow on the cold side as much as controlling the flow through the boiler to end up with a stable showering temperature. It is all about the flow rates not the static pressure, so try using these rather than a PRV.

The shower is mixing cold & hot, if the cold is providing more, you are having to open the hot side up so much that the boiler is not capable of delivering hot water at a high enough temperature for the thermostatic control to work and deliver a suitable shower temperature.

Lots of shower manufacturers use to supply the brown or green restrictors to be put into the cold inlet side to sort this out when you were initialling them.




Sorry slow typist so most of my post already covered. If they are not so worried about other fittings just try a yellow or brown on the cold side as it should bring the shower back in range.

 

[WaterTight]

Lots of shower manufacturers use to supply the brown or green restrictors to be put into the cold inlet side to sort this out when you were initialling them.

Yeah actually I think/hope that's still not uncommon, I've fitted a few within the last couple of years that did.