Starting-up the UFH System.

When the system has been connected to the heat source, all pumps, controls fitted, system has been filled, vented, pressure tested and the srcreed is cured you can start up your UFH.

Loop balancing procedure:

All topmeters should be fully closed at this stage.

Return valves must be fully closed as well (remove thermal actuators if fitted and replace with the white manual caps). Open the first blue cap and adjust the setting of the corresponding topmeter until the design flow rate is reached, by turning the topmeter anticlockwise from fully closed position.

Flow Rates for 16mm MLCP Pipe:


Repeat the process for each loop, then go back and carry out last adjustments, because each loop will have a mutual effect on the others.It's important that the system and UFH Pump are running.

When the topmeter is fully open and design flow rate is not achieved you might have to adjust the pump speed. If removed, refit all thermal actuators.


Set the room thermostats 5°C above the current room temperature so that they call for heat Thermal actuators take some time to be fully open (about 2-4 minutes)

Once you have completed all the above procedures turn all thermostats down to make sure that the system will stop running.

Once it stops, turn up one of the thermostats and wait for the system to start.

That will confirm that the correct loop actuator is open for that particular room. Once the actuator will open turn the thermostat down.

Repeat that process "room by room". This will confirm that every actuator is controlled by the correct thermostat in each room.

As the system is used for first time, the mixing valve must be set to minimum setting to let the moisture in the screed to dry out. The temperature should be increased by 2 degrees every day until the mixing valve is set at 45°C (about 5 days).

Once the mixing valve is set to:

45°C for Screed Floor

55°C for Timber Suspended Floor with Aluminum Spreader Plates

set the room thermostats to required levels and programme the system controls to run as required.