Extending underfllor heating thermostat

[derbyspark]

Hi, i need to extend the probe and power cables to some underfloor heating, can i use 1.5mm for the probes and 2.5mm for the power? the stat is an aube floor sensor with no ambient sensor

many thanks.

 

[robswainelect]

You can extend cables for both thermostat and power with flex of the same size.

 

[derbyspark]

Would it not work with 1.5mm? Problem is i have nothing of similar size.