Central Heating Programmers
Over half of the average UK household’s energy consumption is for heating and hot water. With the cost of energy rising every year, it is important for all of us to take whatever measures possible to reduce our energy usage to save money.
Central heating in general is one of the most energy efficient and cost-effective types of heating system, and the use of a programmer can make it all the more efficient by controlling the times that both heating and hot water are on.
A variety of different programmers are available and which one is best for you will depend on what type of heating system you have, and how you use it.
The difference between programmers and timers
Programmers are usually dual channel systems, which can control both the heating and the hot water independently. Basic timers are more common for single heating systems where the water is heated via an alternative source, or for combination boilers where water is heated as and when needed.
If your central heating also indirectly heats water in a storage cylinder, then you will benefit much more from a full programmer.
Why install a programmer?
There is simply no advantage to running a heating system constantly. Many people believe that if it is controlled by a thermostat, a heating system is more efficient when left on all the time, but this is not true.
If the boiler is continually burning, it will continually be using energy; and if the air temperature outside is cold, the heating will be running intermittently throughout the day to heat the house, even if no-one is home.
A central heating programmer gives you the ability to control what times of day the heating and hot water come on, meaning you only consume energy when you actually need the heating on.
How do programmers work?
Electronic programmers are the most common type in use, particularly with newer systems as they provide the greatest level of flexibility. Most offer a seven day timer with two or three on and off times each day for both heating and hot water. When the timer is ‘on’ the system is controlled by the relevant thermostat; either the room stat or the hot water cylinder stat.
When the temperature drops below the set level on the thermostat, it will ‘call’ for heat and open the relevant motorised valve. This in turn operates an auxiliary switch, which activates the boiler and pump to begin the circulation of hot water.
What types of programmer are available?
There are two main types of programmer on the market, standard electro-mechanical programmers, and fully electronic programmers. Here we will look at products from Danfoss, one of the largest suppliers of central heating programmers.
Standard programmers such as the Danfoss SET3M use a motor driven timing disc, which resembles a clock face, and have programming tappets which can be moved to the desired position to control the times for heating and hot water separately.
It can be considered a single day programmer as it can only operate on a twenty-four hour period. There are also switches to override the timer and set the mode to continuously on or continuously off.
Fully electronic programmers offer much more flexibility, as the heating and hot water can be set against different time bases.
Both can be programmed independently of each other and most electronic programmers include a seven day timer, which allows you to set different on and off times for each day as required. These programmers are much more sophisticated as they are fully electronic and you can set up to three on and off times for both heating and hot water during the day.
The Danfoss FP715 Si, is a full twenty-four hour programmer, with built-in digital time clock. It is high on features and is designed to enable you to make your central heating as efficient as possible.
The unit can be programmed to have up to three on and off times per day, which can be set in a pattern of five weekdays and two weekend days, or seven single days with different settings for each day.
Other features include a service interval alert, a holiday setting for when you are away, over-ride buttons so that you can boost the heating without affecting the set times and built in pre-programmed routines that are ready to use.
Wireless Central Heating Programmers
A wireless central heating programmer is often used when it is impractical to run wiring from the room thermostat to the control system. They operate in the same manner as electronic programmers and use wireless technology to communicate with the receiver and control system.
The Danfoss TP7000RF has all the features of the FP715 Si electronic programmer, with the addition of up to six time or temperature events, which can be set for each day.
How much do they cost?
The Danfoss SET3M standard programmer will cost around £60 to buy, while a fully electronic system such as the FP715 Si will be in the region of £65. A wireless central heating programmer similar to the Danfoss TP7000RF will cost around £110.
Programmers, particularly the electronic types, can have quite complicated wiring systems and it is not advisable to attempt to wire the programmer if you are not familiar with how these systems work.
A qualified electrician should be able to complete the job fairly easily and even with the additional cost of installation, a programmer should save you a considerable amount on your annual heating bill.
Summary
Central heating programmers are designed to give you complete control over the heating and hot water within your home, allowing you to time exactly when they both come on and off to best suit your lifestyle.
Fully electronic programmers are more common in new systems, and offer greater flexibility as they enable a variety of different settings for heating and hot water independently.
If you are conscious of your energy consumption and looking for ways to reduce your usage and therefore your heating bills, installing a central heating programmer is one of the first steps to take towards an energy efficient lifestyle.