Rads not heating up to temperature Help!!!!!

[bhullo]

Hi
I have a glowarm 38cxi boiler and recently the radiators have not been getting that hot they all have tcv on except for the hall, even this one is not getting hot now, the controller is a siemans rev23 digital if you set at 21 deg the boiler kicks in but only half warms the rads then clicks off , hot water is fine.
We live in a flat so only have 6 rads in total .

My question is could it be the rev 23 or is it a pump issue.

Thanks for looking

 

[cross thread]

what setting is the thermostat on the boiler

 

[bhullo]

Hi thermostat on boiler is 55
I have not changed this since we moved in
Thanks

 

[bengasman]

55 is quite low for the boiler, you can easily up that 10 degrees and still get good performance.
It's neither not a pump problem.
What happens if you set the roomstat at 23?
Does the house get warm enough?