water not enough hot

[zetor11111]

Hi all,

I have some problems with hot water in the bathroom. The hot water coming out from the bath tap is only little hot (it's like 50% hot mixed with 50% cold), but hot water in the basin tap is like boiled. Sometimes when I turn on the basin tap the boiler goes into lockout (Boiler - Glow Worm Compact 80e).

Could anyone help me why this happens, please?

Regards

Thomas

 

[Axel]

Is the bath tap a thermostatic mixer type? Or is there a shower valve somewhere in the house that is letting cold mains pressure back through the hot connection? (Faulty / no non-return valve)

 

[zetor11111]

I don't know. How can I check both?

 

[Axel]

It's going to involve shutting off any isolation valves that may be fitted and feeling hot and cold pipes temperature to detect flow in order to diagnose.