Heating Programmers

What are heating programmers?

Programmers are a key component of heating control systems in the UK.

Since many homes are unoccupied for parts of the day, there is little point in heating them if no one is there to benefit. A programmer allows the occupant to specify when the heating comes on to match their lifestyle and their heating requirements.

For many people in the UK, this simply means firing up the heating in the winter months for a couple of hours in the morning, so the house is warm when they wake up, and then firing the heating up again in the evening so the house is warm when they get home until they go to bed.

This means that the heating won’t be on in the interim times, for example during the day when they are at work, or in the middle of the night (although some people do like a warm house even when asleep!).

Programmers range massively in functionality and the choice is often dependant firstly on the type of boiler – combi or heat only. A combi boiler produces hot water on demand whilst a heat-only boiler (despite the name), produces hot water that gets stored in a hot water tank until required.

Two-channel programmers versus single-channel programmers

Honeywell two channel programmerWith a heat-only boiler, you need a two-channel system: one channel that allows you to program when the hot water is being produced and the other for the heating in the home.

For a combi boiler, you only require a single channel programmer – since you are only worried about when the heating comes on.

It is not uncommon for us to encounter boilers that have a malfunctioning two-channel programmer, where the heating and hot water are tied to one another – so when you turn the heating on, the hot water is being produced and vice-versa!

Accuracy of heating programmer

Once you have established what type of programmer you need – a single or dual channel system, then you can choose the functionality you need.

Obviously over the course of a week, people’s heating habits change. For example Monday to Friday it might be very similar, however on Saturday/Sunday, you might require the heating to come on later in the morning.

Drayton single channel programmerThere are essentially three types of programmer that each allow you different levels of control. There are one-day programmers that allow you to specify when the heating comes on each day but every days heating pattern will be mirrored.

So with this type of programmer you might opt for something like this.

  • Mon – Sun                  8:00am  – 10:00am               14:00pm – 23:00pm

These are the most basic types of programmer and while they are simplistic so potentially good for some, in terms of energy saving they are not ideal.

The next type of programmer is the 5-2 programmer, this allows you to set two heating patterns, one for a day in the average working week, and the other for a weekend day (i.e Saturday / Sunday).

So with this type of programmer you might opt for something like this.

  • Mon – Fri                    6:00am – 9:00am                 17:00pm – 22:00pm
  • Sat – Sun                    8:00am  – 10:00am               14:00pm – 23:00pm

Depending on the type of programmer you have it may also allow you to set further time slots for the heating to come on – e.g. instead of just heating the home morning and evening, it may allow you to specify 2 hours in the morning, 2 hours at midday and then a few hours in the evening.

The most advanced (but the one than can most accurately match your heating requirements) is the 7-day programmer and most bought today would be of this type. This allows you to set heating requirements for each day of the week independently.

So with this type of programmer you might opt for something like this (based on the fact that this occupant works from home Tuesday and Thursday).

  • Monday                      6:00am – 9:00am                 17:00pm – 22:00pm
  • Tuesday                     7:00am – 11:00am               14:00pm – 21:00pm
  • Wednesday                6:00am – 9:00am                 17:00pm – 22:00pm
  • Thursday                   7:00am – 11:00am               14:00pm – 21:00pm
  • Friday                         6:00am – 9:00am                 17:00pm – 22:00pm
  • Saturday                    8:00am  – 10:00am               14:00pm – 23:00pm
  • Sunday                       8:00am  – 10:00am               14:00pm – 23:00pm

The good thing about the new programmers is that they allow you to dumb down the complexity if you don’t want it – so if your heating requirements are fairly simple you may just wish to go with 5-7 functionality.

The override button

All new programmers will have an override button, which can give your heating or hot water (if you have a heat only boiler) a boost. If you are using a lot of hot water for example (and you have a hot water tank) you can hit the override button and it will fire up the hot water for an additional hour – allowing you to run more showers or baths.

Programmers working with thermostats and TRVs

You can find more information on thermostats here, but they can be used in conjunction with programmers. The programmer means that the boiler will only fire up as per the times set, however if the house reaches a certain temperature the thermostat will instruct the boiler to turn off.

Working together, thermostats and programmers and TRVs compliment each other to help you tailor your heating demands. This means not heating rooms unnecessarily and also no overheating which helps reduce heating bills.

Taking heating systems a step further you might want to consider intelligent heating control systems which allow you to monitor and change the temperature in individual rooms and learning functionality like Geofencing.

Insulated homes need thermostats – not programmers!

One blog we wrote at the beginning of the year that has proved very popular was on whether it is cheaper to leave your heating on 24/7 or use a programmer/timer to control it. In fact – if you have a well insulated house, it is actually cheaper to leave it on 24/7 and just use the thermostat to control it.

Even so, in reality we would advise people to also get programmers because if you are out of the property for an extended period of time it is worth having ensuring the heating comes on occasionally in winter to stop pipes freezing – the cost of which would far outweigh the energy savings!