Cutting energy costs

Reducing Central Heating Running Costs - Cutting Fuel Bills

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Is it cheaper to run my central heating all day or use the timer?
Generally only use heating when you need it, systems that are run all day raise the average internal temperature of the dwelling, which costs. The more control you have over the time your central heating and hot water are on or off, the more you save on fuel costs. Note the system would have to be designed for this type of 'on off' operation. Ask your plumber to advise on upgrading your controls.

As a rough guide, you can work it out for yourself if you have a gas fired system. First read your gas meter and then run the system for a week using the timer, then read the meter again at the end of the week. Then leave the heating on all day (regulated by the thermostats) for the following week and take another meter reading.

The difference between the readings will tell you which was the most economical, given that the weather was similar for both weeks. This is a useful test for assessing the most effective way for you to heat water, using gas or electric.

How can I set the controls to reduce my running costs?

Reduce the temperature settings: We find that the temperatures customers choose to set their controls at, vary according to their particular needs, but would recommend you set your hot water cylinder thermostat at 60 C (140 F)

Set room thermostat at 18 C - 21 C (65 - 70 F) With young children or elderly in bed, the temperature should not be allowed to fall below 12 C (55 F). For severely disabled people or babies a room temperature of 23 C (73 F) may be more appropriate . Setting your room thermostat down 1 0C can save up to 10% on your fuel bill.
  If you have thermostatic radiator valves these will allow you to set individual radiators to lower settings such as in bedrooms where you may prefer a lower temperature (try setting TRVs on middle numbers and if too hot turn down one notch - if too cool, turn up one notch.) You could even turn them off completely when a room is not in use. If you do, remember to close the door, otherwise warm air will escape into there from the adjoining hallway or landing and reduce any savings. Watch out for condensation/dampness occurring in these rooms though.
Reduce the time the heating is on:
You will probably find that you can save energy without loss of comfort by setting the system to "come on" about half to three quarters of an hour before you get up, and to "go off" half an hour before everyone goes out. Set it to "come on" again half and hour before you get home and to "go off" again half an hour before going to bed.
Is it economical to shut off my radiators?

Yes, you can make savings by turning off radiators during periods when some rooms are not in use but remember to close the doors otherwise warm air will escape into these rooms from the adjoining hallway or landing and reduce any savings. Also you must keep an eye on unheated rooms to guard against dampness or condensation. It is probably wiser just to turn them down.

Also do not turn off the radiator in the same room as the room thermostat, the radiator would give wrong information about the temperature of your home to the room thermostat and affect the heating in the rest of the house. You could consider fitting thermostatic radiator valves in rooms such as bedrooms, which will enable you to maintain individual temperatures perhaps to lower settings than the rest of the house and so make savings in this way. Your plumber will be able to advise on the cost of replacing your existing valves.

What settings should my boiler thermostat be at?
If your system has a room thermostat and a thermostat on the hot water cylinder, set the boiler thermostat on maximum and use these other thermostats to set comfortable room and hot water temperatures. If there are no temperature controls the following are the suggested boiler thermostat settings: NB: If your boiler is behind the gas fire the boiler thermostat can be found behind the flap at the bottom of the fire.
I have a boiler back unit. Is it cheaper to run the boiler or the fire?
  It is only worthwhile using the fire on its own for heating when you don't want to heat the whole house, perhaps between seasons such as early spring when outside temperatures start to rise and are less predictable. The boiler produces more heat and so uses more gas but of course, heats the whole house including the hot water.
What percentage savings can be made if I..
Insulate the loft.
Have cavity walls fitted.
Fit double glazing?

Insulating your loft is one of the most worthwhile places to spend money to prevent heat from escaping.25% of the heat lost in homes escapes through the roof. Up to 35% of the heat in a home is lost through walls. Filling cavity walls reduces heat loss from 35% to 10%Even if windows are properly draught-proofed about 20% of heat is lost through a closed single glazed window. Installing double-glazing would halve heat loss through windows. The cost of double-glazing varies greatly from a cheap and fairly temporary method, such as fitting cling film (i.e. temporary secondary glazing), to having complete windows and frames replaced.

In summer is it cheaper to heat hot water all day or heat the water for short periods as required?
1   It is generally cheaper to heat hot water only when you require it. If a cylinder is properly insulated, hot water will keep hot for up to 12 hours, so set the boiler to operate at times when you need to draw off large amounts of hot water. If you do not have a cylinder thermostat, ask a plumber to fit one, you will recoup the cost though savings in a relatively short space of time.
When thermostats are turned down, radiators to not become warm below certain temperatures - in some cases this can be as high as 20°C
Radiators are only heated when the boiler is 'on', the radiator valves open, and the time clock is switched to "on". Even then if the room thermostat senses that the room temperature is at the required level, the boiler will not come on.If the room thermostat is set at 20 deg.C and senses that the room temperature is registering 20 deg.C , then the boiler will not operate and the radiators will cool down. The radiators will remain cool until the air temperature falls and the room thermostat calls for more heat.

Note: If radiators are heating up unevenly they may need "bleeding".