Some zones do not become warm
Air trapped within pipework
Set the UFH pump to speed setting III, open the balancing valve fully for the problem zone ensuring all other zones are isolated. Air should automatically vent from the system.
Manifold incorrectly balanced
Please refer to our installation manual section 4.1 on Circuit Balancing.
Primary flow and return pipes crossed
Check the flow and return pipes from the heat source are correctly connected to the manifold and that they are controlled by the correct thermostat