Problem with under floor heating

[AJH]

I have a boiler with a standard CH and WH control timer.
I also have an under floor heating system (water) with thermostats in every room of the house controlling each room independently for temperature.

I have found that when my kitchen thermostat demands heat, my lounge and 1 bedroom also get heat. This is not a system setup issue as all rooms used to work independently.

Any ideas of the cause and how to fix?

 

[ShaunCorbs]

Motorised valve could be at fault if it's been working fine all depends on how it was installed

 

[rpm]

Welcome to the forum AJH.

 

[Rybo_1]

Possible problem with actuator heads