Controls
Controls decide when the boiler runs and how hot it runs. These entries cover thermostatic valves, room thermostats, timers, flow temperature and frost protection, with who may change what.
- Thermostatic radiator valve
A thermostatic radiator valve, or TRV, senses the temperature around it and adjusts the flow of hot water into that radiator, so each room can run at its own setting.
- Room thermostat
A room thermostat measures the air in one room and switches the heating on or off to hold the temperature you set.
- Programmer and timer
A central heating programmer or timer switches your heating on and off at times you choose, and on systems with a cylinder it may also time the hot water.
- Flow temperature
Boiler flow temperature is the temperature of the water leaving the boiler for the radiators, and government advice for combis is to reduce it to 60°C.
- Weather compensation
Weather compensation on a boiler varies the heating water temperature according to the outside temperature, raising it on cold days and lowering it on mild ones.
- Zone valves
A zone valve in central heating is a motorised valve that opens or blocks hot water to one part of the system, so areas can be heated separately.
- Frost protection
Boiler frost protection is a built-in function that runs the pump or burner when the boiler gets very cold, and it generally needs the power left on.