This gets bandied around quite a lot and with good reason as it is the single biggest action you can take to save on gas usage. If you’ve already insulated your house a few years ago, it may be worth reviewing again to see if what was too costly to insulate before is now worth doing given the increase in the price of gas.
Insulating also includes sealing all gaps where cold air can come through. So this includes around skirting boards on a timber ground floor, external doors not closing properly, around pipes that go through external walls if the cement is cracked or has fallen out, gaps around window frames, and so on. I’ve even found that euro cylinders conduct heat out of the house as the internal surface had cooled to such an extent that condensation had formed all over it. Now when are Building Regs going to come up with something for that?
Afterwards, don’t forget to open windows now and then in the middle of winter to get some fresh air and ventilate the house!
Another big tip is installing big radiators. I mean really big ones, oversized ones.They are costly yes, but if you’ve previously discounted them on the grounds of cost, perhaps now it would make more sense? You could also try getting second hand radiators.
Why are bigger radiators better? Simply because they emit more heat. Imagine trying to heat a room with a small heater versus underfloor heating. This leads me to my next tip which goes hand in hand with bigger radiators:
Reduce the temperature of the water leaving the boiler for heating radiators to as low as possible. Only with oversized radiators will it be possible to lower this flow temperature significantly. Traditionally the flow temperature used to be around 80 deg but you could go down to 50 deg or lower if you have oversized radiators installed. In fact, the new regulations require the flow temperature not to exceed 55 deg in new heating installations and this can only be achieved with big enough rads.
Why is this so important? If you only need to heat water to 50 deg, then you burn significantly less gas. This low temperature also causes the boiler to go into condensing mode, meaning it will “squeeze out” more heat from the flue gases that escape into the atmosphere, otherwise this is just wasted heat.
You don’t need a gas engineer to lower your flow temperature. However, on some boilers, this feature is hidden deep in the menu. You could also adjust the flow temperature up and down as required, so when it’s slightly cold outside, the temperature could be set very low as the house doesn’t need to be heated much. On very cold days, ramp up the flow temperature to keep the house warm.
Boilers work best when they keep running, instead of being turned on and off. This is because it reduces wear and tear on the boiler, through expansion and contraction of the components. It’s a bit like driving a car through town and having to stop constantly at red lights versus cruising on a clear road in 5th gear. So set the flow temperature low enough that the boiler needs to run all the time. Remember, if the flow temperature is low enough, the boiler will be using very little gas.
This tip applies to combi boilers. Note that system and heat only boilers require a temperature of no less than 60 deg to heat the hot water cylinder to prevent legionnaires’ disease.
Most combi boilers have a preheat function. This is used to keep the water from your tap hot so that you don’t have to wait a long time when you open it. It also means water may be heated unnecessarily if you’re not at home all day long. It’s not a big saving but over time may add up.
There are many properties with suspended timber ground floor having heating pipes running under them. It’s easier to run the pipes in the void under the floor than hack channels into the walls from the ceiling down to the rads and looks far neater than pipes running over the wall. However, those voids are cold and these pipes are rarely adequately insulated, if at all. Not only do they then lose a lot of heat but they are at risk of freezing. They are also rarely adequately supported by pipe clips as it is awkward to fit them. In the even of a leak at a joint because of this, it may never be detected because the leak will be outside the property.
The solution is to run the pipes inside and you won’t even have to insulate them. It’s not as pretty but if you’re intent on saving on gas bills, that’s the way to go.
Make full use of thermostatic radiator valves (TRVs). Just having them fitted is not enough – it’s not a case of fit and forget anymore. TRVs serve to adjust the temperature of individual radiators. So if there’s a room you don’t use much during the day, for e.g. a bedroom, you can lower the temperature of the radiator in that room or even shut it down altogether, otherwise you’re just heating a room unnecessarily. It’s a bit of a hassle having to go round and fiddling with TRVs everyday but again, if you want to save on gas bills, that’s the way to go.
Don’t forget to heat every room properly from time to time otherwise mold may start to make its appearance.
Get a gas engineer to range rate your boiler at the next service, or check that it is range rated. Range rating means adapting the heat output of a boiler to the heat input required of a property.
When sizing a boiler, its heat output is dictated by the hot water flow rate at the taps, not the heating. If a house is well insulated, for instance a new build, the heating requirements will be very low compared to the heat required for hot water. A relatively big boiler will still need to be installed to cope with the hot water requirements, but it will be way too big for the heating.
By range rating it, the gas engineer will reduce its maximum heat output for heating. This helps the boiler use less gas and run for longer, rather than start and stop because temperature has been reached quickly. Range rating is just an extra protection as if you follow tip #3 and reduce the flow temperature, the boiler should not deliver excess heat.
Electricity is far more expensive than gas, so where possible, try to use gas instead of electricity, unless you get free electricity, via solar panels for instance. You may be tempted to heat a room only with a single small electric heater; use TRVs instead to shut down other radiators and don’t forget to heat the full house from time to time. Electric cookers and showers are very expensive to run, try using your gas boiler instead for showering and a gas cooker.
There are now induction hobs which are meant to be very energy efficient – the pots themselves get heated directly via a magnetic effect. The hob surface is even cool to touch, unless the hot pot itself has been in contact with it. However, an induction hob will still require its own dedicated electrical circuit from the consumer unit and an adequately thick cable to carry a large current. In other words, it still uses a lot of electricity. So while induction hobs are always being marketed as energy efficient, and it may be in that heat is not lost, it still uses a lot of energy.
This is a rather controversial tip when people are being told to make sure they have a thermostat fitted and to use it, or even to upgrade to smart controls that set the heating on for you as and when needed.
My argument is that only you know when you feel cold or hot. If you’re working from home all morning and sitting down, you’ll want a warm environment. If you’ve decided to go to the gym in the morning, not only will you not be at home then, but upon your return you’ll feel hot. If you’ve been moving around cleaning the house all morning, you’re not going to feel cold. In these situations, it may be better to switch on and off the boiler as and when required rather than let a timer or thermostat dictate when the heating has to come on. Use of a thermostat is still a good idea in case you forget to switch off the heating manually. The thermostat will do it for you when it reaches temperature.
This setup will only work well if there are few people in the house and will depend upon your lifestyles. For instance if someone is working from home all morning whilst another just came from the gym, you’re going to have to compromise. Oversized radiators and good insulation also help to heat the house quickly, so if you’ve just come back or woken up, you can get the house warm in a few minutes without having to heat it up beforehand.