My hot water is scalding in the summer but OK in the winter, what’s wrong?
This is probably caused by using two different sources for your hot water over the year. In winter the hot water will probably come from the central heating boiler which has a thermostat attached to it. This is usually set at about 60°C. However, during the summer many people switch the boiler off and rely on an immersion heater for the hot water. This should also be set at 60°C but could have been set at the factory at 80°C.
Why does it take a long time for the hot water to reach my taps?
The problem is related to the length of piping there is between the cylinder, or combi boiler, and the hot water tap. In some cases, such as very large houses, the solution may be to install a pump to circulate the hot water, but in the average home this is usually impractical. The best solution is to site the boiler in a central location between the rooms that use hot water the most.
Is it more efficient to have a large hot water cylinder or a small one?
In simple efficiency terms a smaller cylinder is best, as it loses less heat and you’re more likely to use all the water that you’ve heated. If you’re using a central heating boiler, it’s even more efficient to have a large heat exchanger inside the cylinder, known as a rapid recovery cylinder. This means that all the heat produced by the boiler will be used to heat the water quickly.
In cost terms, however, you’ll have to consider the type of fuel you use and how much hot water you’re using. If you use a lot of hot water and heat it with an electric immersion heater then it would be cheaper to have a larger cylinder and heat it over night on an off peak tariff. This would avoid or reduce the need to top it up using expensive day rate electricity.
My cylinder takes too long to heat up
If it used to be OK you may be suffering from limescale problems – establish if hard water area and how long cylinder has been installed.
Won’t turning my hot water heater on and off cost me more in the long run?
No. Water heaters use more energy to heat water and maintain a high temperature for an extended period, than they do to heat it up the once.
Is a combination boiler more efficient than a conventional boiler?
Not necessarily – It is important to match your choice of system to your heating and hot water needs. A qualified installer can let you know which is most suitable.
If I put more insulation on my cylinder will my clothes still air properly?
Yes, the airing cupboard will still get sufficient heat to remove dampness.
