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Control of Your Gas Central Heating System

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Programmer / Timer

What does a programmer do?

It allows you to set times for your heating to come on and go off to suit your lifestyle.  Once set, the programmer automatically controls the times at which your central heating system switches on and off. There are generally two types of programmer / timer, a manual clock with tabs to set the timing periods and an electronic one (see examples below). Make sure that the programmer / timer is set to the correct time of day. If you have a combination (combi) boiler then you will only set the heating periods for the radiators as hot water is heated instantly when the hot water taps are opened.

What times should I set my programmer to come on and off?

It really depends on you and your lifestyle.  Its best to set your heating to come on about half an hour before you want your home warm, and to go off about half an hour before you go out or go to bed. Ideally you should run the system in two periods and for no more than 9 hours per day in total.

Manual Programmer / Timer for combi boiler – times the radiator heating only

Manual Programmer / Timer for non combi boiler – times the radiator and hot water heating.

Manual Programmer / Timer for non combi boiler – times the radiator and hot water heating.

Room Thermostat (Where fitted)

A room thermostat looks something like the one in the photograph here. It will have a dial with a range of temperatures on it.

How does a room thermostat work?

Room thermostats can usually be found in the living room, hallway or dining room. It controls the temperature of your whole home based on the temperature of the air circulating around the home. When the air around it is warm enough, the thermostat sends a signal to the central heating pump and boiler to stop firing and circulating water around your pipes to your radiators. Your radiators will then cool down.

What temperature should I set my room thermostat to?

It depends on you and your situation.  If you're a pensioner or infirm then your room thermostat should be set at 21°-23°C (70°-73°F), otherwise 18°-21°C (66°-70°F) is fine for healthy adults.

Thermostatic Radiator Valves

When the air around your room thermostat cools the thermostat sends another signal to the central heating pump and boiler to start heating up water again to pump around your pipes to your radiators.  Your radiators will then warm up again. Throughout the day your radiators will feel cooler and warmer to keep the temperature constant.

Check that the thermostatic valves on the radiators and time clock are set at the desired temperature and time. It's best to set your TRV to a middle setting and see if the room is warm enough.  If the room is too warm, turn the TRV down by 1, if the room is too cold, turn the TRV up by 1.  A middle setting corresponds to approximately 20°C (68°F).Do NOT turn the TRV fully ON or fully OFF to make the room you are in warmer or cooler - this will waste fuel.  Turn it a little way and let it do the work.

Boiler Thermostat

This is a control found on the boiler itself.

It controls the temperature of the hot water flowing around the pipes to the radiators.

How should I set my boiler thermostat?

The boiler thermostat could be rated differently from one boiler to another. The boiler will operate most efficiently on the MAX / HIGH setting. It should be set on HIGH / 5 in winter and LOW / 1 in summer.

The Electricity Pump

This is generally located near the time clock and, in order for water to be circulated to the radiators, must be switched on.

Hot Water Tank

How can I insulate my hot water cylinder?

You can buy a jacket for your hot water cylinder from your local DIY store.  This is one of the simplest and cheapest things you can do to cut your fuel bills and save energy.  Some cylinders already have foam sprayed on them and so do not need a jacket.  It is also worth insulating the pipes that enter and leave the cylinder - you can get foam tubes for doing just this. Do it as far back from the cylinder as you can reach.

What controls the temperature of my hot water?

If you have a hot water storage cylinder, it will usually be fitted with a thermostat to control the water temperature.  For water that is heated by an electric immersion, the thermostat will be inside the tank. If you heat your water with a combination (combi) boiler, the heating control for your water is on the boiler.


At what temperature should the cylinder thermostat be set?

The temperature you select will determine the temperature of the hot water coming out of the hot water taps.  Ideally, it should be set to 60°C (140°F).  (Certainly not lower than 55°C as this could cause legionnaires disease.)

If your boiler is not working

Carry out the following simple checks.

Information for new tenants of WCBC properties

If you move into a property, which has been tenanted previously, the instructions for how to operate the heating system may not be available, if required one of WCBC’s gas contractors will explain the controls to you during the gas safety check.

If you do not understand the system and you have no neighbours with similar systems who you can ask, please ring the estate office and ask for someone to call and explain it again to you. If you are sure that you do understand the system and it is not working properly, please check the simple checks above before you contact the office.