Once the system is installed and up and running, it will be necessary to carry out Underfloor Heating Flow Rate Adjustment to balance the system. This should be done using the following method:
- Open the manifold valves on the manifold; ensuring that the water temperature is at the correct temperature on the blending valve, using between 45ºC & 65ºC. Caution, due to the operating of the blending valve, the flow of water from the boiler should be at least 15ºC hotter than the blending valve setting. For example; if the underfloor heating system is set to a required temperature of 45ºC, the flow temperature must be minimum 60ºC.
- The Underfloor heating pump should be set for a fixed speed using the pump adjustment facility. Now you can begin with Underfloor Heating Flow Rate Adjustment. Remove the red caps on the flow, or top, bar of the manifold. Turn the valve anti-clockwise to decrease the flow rate. Likewise, turn the valve clockwise to increase the flow rate. Adjust each circuit until the flow meter on the flow until set up is complete. You can adjust these the flowmeters at any time if required.
Troubleshooting Underfloor Heating Flow Rate Adjustment
If you fault once the system is up and running, the first thing to check is the flow rate. They should be set between 1.5L/min and 2L/min for boiler use and 1L/min for heat pump use.
See below list for a checklist of issues and solutions.
|No Circulation||Check Flow meters are open; fully open to check the flow of water if required.|
|Flow and Return pipes are hot but not enough heat in room||Too much flow. Reduce flow rate to allow a slower flow and a higher heat transfer rate into the floor.|
|No heat in rooms||Is your system working? Check pump is running and thermostats calling for heat. No changes required to flow meters|
|Some rooms hot, the others are cold||Insufficient flow in colder rooms. Increase flow rates in rooms requiring more heat.|