Combi Boiler Room Thermostat Wiring

The choice will depend on the boiler.

Combi boiler room thermostat wiring.

3 wire thermostat and programmer. The boiler will have a terminal which activates the boiler when mains voltage is applied to it typically labelled sl or switched line. Combination boilers and connecting thermostats to them including hive and nest. This guide shows you how to wire up a thermostat watch this and other related films here.

For those boilers which have a programmer or timer built in the only other device required is a room thermostat. A wireless thermostat is a digital device that can tell you the temperature of its surroundings. Here the neutral is shown from the boiler however it could be provided via the programmer if this is more convenient. These boilers require a mains voltage thermostat which can have 2 or 3 wires.

The boiler only operates if both the programmer and thermostat are on. This is the same switching arrangement however here a 3 wire thermostat is used which requires a neutral connection. The circulator pump for the central heating is normally an intergral part of the boiler so no additional wiring is required. The thermostat to the boiler or pass through a junction box if there s a combi boiler with no junction box the heat link will be connected directly to the boiler s control circuit you may need to test each cable to understand its function make sure you connect the correct cables to the heat link to avoid blowing a fuse 10.

This is my video on how to wire a nest learning thermostat with a combi boiler it s super simple once you know the set up. It does this using electronic sensors and can communicate with the boiler to provide the ideal room temperature for yourself. Here are all the products i used. Also covers volt free contacts and why mains voltage must not be connected t.