Shower not getting hot water

[njmorrison]

Hello all, I visited a house today with two on-suite showers which both are not getting hot water through! The showers are both mixer valves with dual controls. I removed the temperature knob on both showers to make sure they hadn't been put on incorrectly and turned the knob all the way to the maximum hot and the water coming out of the shower was slightly tepid. It was exactly the same on the other shower. It's a new build of about two years old and has a vailant combi boiler. I wasn't able to spend any time on the problem but will be going back on Tuesday to try and figure it out. Apparently both showers did work perfectly ok and have gradually got cooler and cooler over the last couple of months! Any suggestions?

Thanks

 

[helpsy]

Thermostatic cartridges?
Filters?

 

[REDSAW]

filters blocked with debris,
if u can take of hot feed pipe (you may have to to check filter anyhow),
and see if hot water pours out of pipe when open ended.