New Grohe Avensys shower not getting hot

[bygravey1]

Have renovate by en-suite and acquired a Grohe Avensys Modern Concealed Shower Mixer 34224 off ebay. Very nice piece of kit The shower is fed from a combination boiler and mains cold supply. At first you could still just about get the shower hot enough but only by turning the on-/off lever back, the temperature lever didnt allow the shower to get hot enough when fully on. Then after while it has stopped getting hot at all and only releases cold water. The previous non branded mixer worked a treat & the adjacent basin provides piping hot water. I correctly connected to the right H/C inlets so not sure why, any ideas?

 

[denso13]

Does it get hot if you run the basin hot at the same time? Also take of the shower head and see it gets hot with an open end on the shower hose.

 

[bygravey1]

Hi thanks nope both do not impact stone cold despite basin adjacent and piping hot...

 

[denso13]

Do you have the manual? You can normally adjust the hot temperature setting as part of the installation.

 

[polesapart]

 

[bygravey1]

I just snuck in a couple of isolator valves and cold washes through fine but when I turn off the cold the hot doesn't go through at all as if its blocked.Took the brass connectors off and they look clear. So not sure?

 

[denso13]

when I turn off the cold the hot doesn't go through at all as if its blocked

On an open isolator valve? If so something's not right and you'll need to start tracing the pipe backwards and checking for hot water at different points.

 

[bygravey1]

The isolators are just before the shower inlets and when open and not connected to the shower they run fine, hot out of the hot and cold out of the other

 

[bygravey1]

For closure - Proves not a supply issue as have replaced with another unit (which is a Grohe as well) as cannot wait for Grohe to come our via the warranty.