Heating

It is now widely accepted that installing a high efficiency condensing boiler will help save considerable sums of money. Over 80% of energy used in the home is for heating and hot water so it makes sense to install the most efficient boiler which is “A” rated.

There are currently over 4 million older “G” rated boilers still operating at less than 60% efficiency, by replacing them with “A” rated boilers will save over £300 per year on the fuel bill. These older boilers are easily recognised by the permanent pilot light, so if you have one of these it will definitely be over 15 years old and you should consider replacing it now.

The Heating and Hot Water Industry (HHIC) website can help you obtain impartial and informed advice about domestic heating systems.

Our reference library will enable you to research and find answers to all a wide range of domestic heating and hot water problems. For example, if your boiler has broken down or you would like to install renewable heating systems, then we can definitely help. You can start exploring the site by clicking on any of the highlighted sections:

Heating Types

  • Do you know what a ground source heat pump is?
  • Do you know how your boiler works?
  • Do you know the difference between a combi and a standard boiler?

Click here for explanations on how various heating types that can be used for domestic heating work and how they should be used.

This section will be especially useful if you are looking to buy a new heating system or if you are looking at some of the exciting renewable alternatives.

Heating Advice

Our Heating Advice section is a library of questions we have been asked and our responses. Please use this search facility to see if these questions could help you with your heating enquiry.

Checklists

In order to guide you through some of the common concerns with regards to heating we have devised a number of checklists

Buying a New System

  • This explains how to approach buying a new system, renewable or conventional. It provides guidance on what to expect in a quote, qualifications needed and questions you should ask.

How Legislation Affects You

  • Guidance on current legislation and how it will affect you and your heating system.

Heating Maintenance

  • Advice on how you should maintain your heating system to help keep it working efficiently.

What Do I Do If

Answers to a few very common problems.

Heating Controls

If you want to save energy in your home then it is obvious that you need to start by identifying where most energy is used. In most homes, 84% of energy is used to provide heating and hot water, and these areas account for about 70% of the carbon emissions.

It’s also obvious that your heating needs to be controlled so that it uses the minimum amount of energy to keep you warm. A basic set of heating controls can reduce your energy bills by nearly a fifth and should achieve the following:

Automatically turn off heating when not required

This is usually referred to as ‘time control’ and generally requires a programmer to switch your heating off when you’re not at home, or when you can do without it, such as when you’re in bed.

Automatically prevent the building getting warmer than it needs to be

This is usually referred to as ‘temperature control’ and generally requires a room thermostat. This should allow you to set a comfortable temperature and then automatically turn the heating off when that temperature is achieved. The heating will therefore only come on to maintain the comfort temperature that you require. A programmable room thermostat will combine time and temperature control and allows you to set different temperatures for different times of the day.

Avoid overheating parts of the house that are unoccupied or need lower temperatures

This is referred to as zone control. Separate zones are usually set to provide lower temperatures in bedrooms but can also be used to take advantage of ‘passive solar gains’ in rooms with lots of glazing, or to flexibly accommodate specific usage patterns such as a home office or granny flat. Zones are often provided through the application of thermostatic radiator valves, but can also be done with separate heating circuits each with their own programmer and room thermostat (or programmable room thermostat.

More information on the controls to provide these functions is provided below:

What is a programmer?

Programmers allow you to set ‘On’ and ‘Off’ time periods. Some models switch the central heating and domestic hot water on and off at the same time, while others allow the domestic hot water and heating to come on and go off at different times.

Set the ‘On’ and  ‘Off’ time periods to suit your own lifestyle. On some programmers you must also set whether you want the heating and hot water to run continuously, run under the chosen ‘On’ and ‘Off’ heating periods, or be permanently off.

The time on the programmer must be correct. Some types have to be adjusted in spring and autumn at the changes between Greenwich Mean Time and British Summer Time.

You may be able to temporarily adjust the heating programme, for example, ‘Override’,  ‘Advance’ or ‘Boost’. These are explained in the manufacturer’s instructions.

The heating will not work if the room thermostat has switched the heating off. And, if you have a hot-water cylinder, the water heating will not work if the cylinder thermostat detects that the hot water has reached the correct temperature.

What is a room thermostat?

A room thermostat simply switches the heating system on and off as necessary. It works by sensing the air temperature, switching on the heating when the air temperature falls below the thermostat setting, and switching it off once this set temperature has been reached.

Turning a room thermostat to a higher setting will not make the room heat up any faster. How quickly the room heats up depends on the design of the heating system, for example, the size of boiler and radiators.

Neither does the setting affect how quickly the room cools down. Turning a room thermostat to a lower setting will result in the room being controlled at a lower temperature, and saves energy.

The heating system will not work if a time switch or programmer has switched it off.

The way to set and use your room thermostat is to find the lowest temperature setting that you are comfortable with, and then leave it alone to do its job. The best way to do this is to set the room thermostat to a low temperature – say 18oC – and then turn it up by one degree each day until you are comfortable with the temperature. You won’t have to adjust the thermostat further. Any adjustment above this setting will waste energy and cost you more money.

If your heating system is a boiler with radiators, there will usually be only one room thermostat to control the whole house. But you can have different temperatures in individual rooms by installing thermostatic radiator valves (TRVs) on individual radiators. If you don’t have TRVs, you should choose a temperature that is reasonable for the whole house. If you do have TRVs, you can choose a slightly higher setting to make sure that even the coldest room is comfortable, then prevent any overheating in other rooms by adjusting the TRVs.

Room thermostats need a free flow of air to sense the temperature, so they must not be covered by curtains or blocked by furniture. Nearby electric fires, televisions, wall or table lamps may prevent the thermostat from working properly.

What is a programmable room thermostat?

A programmable room thermostat is both a programmer and a room thermostat. A programmer allows you to set ‘On’ and  ‘Off’ time periods to suit your own lifestyle. A room thermostat works by sensing the air temperature, switching on the heating when the air temperature falls below the thermostat setting, and switching it off once this set temperature has been reached.

So, a programmable room thermostat lets you choose what times you want the heating to be on, and what temperature it should reach while it is on. It will allow you to select different temperatures in your home at different times of the day (and days of the week) to meet your particular needs.

Turning a programmable room thermostat to a higher setting will not make the room heat up any faster. How quickly the room heats up depends on the design of the heating system, for example, the size of boiler and radiators.

Neither does the setting affect how quickly the room cools down. Turning a programmable room thermostat to a lower setting will result in the room being controlled at a lower temperature, and saves energy.

The way to set and use your programmable room thermostat is to find the lowest temperature settings that you are comfortable with  at the different times you have chosen, and then leave it alone to do its job. The best way to do this is to set low temperatures first, say 18oC, and then turn them up by one degree each day until you are comfortable with the temperatures. You won’t have to adjust the thermostat further. Any adjustments above these settings will waste energy and cost you more money.

If your heating system is a boiler with radiators, there will usually be only one programmable room thermostat to control the whole house. But you can have different temperatures in individual rooms by installing thermostatic radiator valves (TRVs) on individual radiators. If you don’t have TRVs, you should choose a temperature that is reasonable for the whole house. If you do have TRVs, you can choose a slightly higher setting to make sure that even the coldest room is comfortable, then prevent any overheating in other rooms by adjusting the TRVs.

The time on the programmer must be correct. Some types have to be adjusted in spring and autumn at the changes between Greenwich Mean Time and British Summer Time.

You may be able to temporarily adjust the heating programme, for example, ‘Override’,  ‘Advance’ or ‘Boost’. These are explained in the manufacturer’s instructions.

Programmable room thermostats need a free flow of air to sense the temperature, so they must not be covered by curtains or blocked by furniture. Nearby electric fires, televisions, wall or table lamps may prevent the thermostat from working properly. 

What is a thermostatic radiator valve (TRV)?

TRVs sense the air temperature around them and regulate the flow of water through the radiator which they are fitted to. They do not control the boiler.

They should be set at a level that gives you the room temperature you want. These settings may have to be different in each room, and you should set the TRVs to suit each room and then leave them to do their job.

Turning a TRV to a higher setting will not make the room heat up any faster. How quickly the room heats up depends on the boiler size and setting, and the radiator size. Turning a TRV to a lower setting will result in the room being controlled at a lower temperature, and saves energy.

TRVs need a free flow of air to sense the temperature, so they must not be covered by curtains or blocked by furniture.

TRVs cannot turn off the boiler when the whole house is warm. To do that, you will need a room thermostat as well. The radiator in the room with the room thermostat should not normally have a TRV, but, if it does, keep the TRV on the maximum setting and adjust the room thermostat as explained with the instructions.

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