What are heating controls?

Whether your home has a stored hot water system or a combi boiler, there are different types of heating controls of all shapes and sizes…

We'll show you what they look like, what they do, where you might find them and how they work together in a central heating system.

house with heating systems and a magnifying glass on it Take a closer look at the heating system
Stored Hot Water System Combi Boiler System
Hot water system

Heating

1. Time

Set the programmer to come on when you need heating

2. Temperature

Set the room thermostat to the required temperature

3. Flow

The valve opens to direct the flow of water to the radiators

Hot water

4. Time

Set the programmer to come on when you need hot water

5. Temperature

Set the cylinder thermostat to the required temperature

6. Flow

The valve opens to direct the flow of water to the cylinder

Stored Hot Water System Combi Boiler System
Combi boiler system

Heating

1. Time

Set the time switch to come on when you need heating

2. Temperature

Set the room thermostat to the required temperature

3. Flow

The boiler fires and hot water is pumped to the radiators

Hot water

Water is heated

by the heat exchanger in the boiler to provide instant hot water on demand

No time control

Instant hot water

No temperature control

no external temperature controls - Hot water temperature control set within the boiler

No flow control

Hot water is instantly heated by the boiler

Time Controls

There are various types of timers, and they are called different things dependent on what you use them for. A time switch controls one type of operation, either the heating of one zone or the time hot water is available. A programmer integrates the control of heating and hot water into one unit giving you two channels that you can independently set to provide time control for either heating or hot water. You may have a time control near your boiler, or in your airing cupboard close to your hot water cylinder.

Features of Modern Controls What is Zoning?
Yours may look like this...
Time control Time control Time control
Time control
See our range of Time controls

Temperature Controls

A room thermostat lets you control the temperature of your home. You may have either an analogue dial thermostat or a modern digital thermostat.

Your thermostat can often be found fixed on a wall in the hallway or landing, where it senses the overall ambient temperature. Alternatively, if your thermostat is wireless it can be moved around the home to accurately measure desired temperature in any given room.

Features of Modern Controls What is Zoning?
Yours may look like this...
Temperature control Temperature control Temperature control
Temperature control
See our range of Thermostats

Combined Time and Temperature Controls

Programmable thermostats give you a greater level of control by letting you set different desired temperatures at different times of the day. They are used to control the heating part of your central heating. They are not used to control the time or temperature of your hot water.

Yours may look like this...
time and temperature control time and temperature control
time and temperature control
See our range of Programmable Thermostats

Radiator Valves

Modern thermostatic radiator valves (TRVs) can be fitted to individual radiators. They have a built-in temperature sensor and should be used together with a room thermostat to accurately control the room temperature.

TRVs work by automatically opening and closing the flow of hot water into the radiator to keep the room at a desired temperature. They don't turn the boiler on or off.

More about TRVs
Yours may look like this...
Radiator Radiator Radiator
Radiator
See our range of TRVs

Hot Water Cylinder Thermostat

A cylinder thermostat controls the temperature of stored hot water in a cylinder (also known as a hot water tank).On a vented hot water cylinder it sits directly on the outer surface of the cylinder, usually cut into the insulation. If you have an unvented cylinder your cylinder thermostat will be inserted into the cylinder through a special aperture.

Both types of cylinder thermostat then send data to the timer control, which tells your system when to switch on or off.

If you have a combi boiler, you won’t have a hot water cylinder thermostat.

More about Cylinder Thermostats
Yours may look like this...
How water cyclinder thermostat How water cyclinder thermostat How water cyclinder thermostat
How water cyclinder thermostat
See our Cylinder Thermostats

Zone Valves

Zone valves control the flow of hot water to the radiators and hot water cylinder. They are controlled by other system controls such as a time switch; programmer or multi zone controller. Zone valves can also be used to divide the home into two or more zones, for example, a downstairs zone heated during the day and an upstairs zone heated at night – increasing your energy efficiency!

Features of Modern Controls What is Zoning?
Yours may look like this...
Zone valves Zone valves Zone valves
Zone valves
See our Zone Valves

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