Underfloor Heating Installation in Winter

7th December 2015 0 By ThermoUFH

Underfloor Heating can be installed throughout the winter months as long as a few guidelines are followed.

Underfloor Heating Pipes by their nature are very robust, however, there is always a good chance that the pipe could burst in freezing conditions. A punctured pipe is really not worth the risk, the screed would need to be dug up to find the leak, repair the pipe, pressure test then reinstate the screed. There is always the risk that frost can cause damage to the UFH Manifold and Pump too.

There are options to prevent the risk of freezing:

1) Once the underfloor heating is laid, then it can be pressure tested using a water and inhibited antifreeze mix. Our FloorHeating Supplies Heat Transfer Fluid (HTF50) is ideal for this purpose as it contains Antifreeze, Inhibitors and Biocides to protect the system even when up and running. It is available to buy on our website and offers protection from -5°C to -50°C depending on concentration. It can be added to your system using a Solar Filling Station or submersible pump in a clean bin / water butt.

2) The Heating System can be pressure tested with air, this can be an issue with flowing screeds, however, as the pipes want to float in the liquid screed.

3) Pressure test the system as normal with water, once the screed has been laid and the integrity of the system is checked then you can drain the system down, using air to push the water out of the loops. This means you will be doing the filling and bleeding process twice but is still better than a damaged pipe.

4) You can hire temporary boilers that will run the underfloor heating, preventing the pipes freezing and drying the screed at the same time. This can be done after 7 days with flowing screed and 28 days with traditional screed.

It is our recommendation that option 1 above is the ideal to protect your underfloor heating during the winter months. Our HTF can be left in the system and it is generally a condition of the warranty on the boiler that an inhibitor is used. Our HTF50 contains inhibitor so is ideal for this purpose.



For further information on any of our underfloor heating systems, and a bespoke quotation for your project please call our technical team on 01204 61669.