Heating System

[tooj]

Over the cold spell we've had our heating on at 20 degrees all day. We are finding that after a while when we turn the hot tap on the water comes out scalding hot. Can this be cured without calling in the heating engineers?

[bhg481]

If you have a system with a hot-water cylinder (as opposed to a combi boiler, about which I know nothing), there should be a thermostat on the side of it. The normal operation of these systems is to heat the water first then, when the thermostat temperature is reached, switch the water-flow to go to the radiators. You should be able to turn down the cylinder thermostat to 55-60 deg.

[EDDIE51]

If your hot water storage cylinder is like ours it has a thermostat on it.
That thermostat controls the water temp ( mine is set to 60 Deg) and the room thermostat controls the room temperature. ( again mine is set to 20 deg)

[diddlydo]

We have a hot water cylinder with a thermostat on the outside which, in the winter, we set at 45 degrees. The hot water is still scalding when we have the heating on. Gas engineer says "nothing wrong with it"!

[Kidas]

Government advice is to maintain hot water cylinders above 60°C to avoid spread of legionnaires' disease

http://www.hse.gov.uk/healthservices/legionella.htm

At 45°C you risk allowing the bacteria to grow in the dead circulation parts of your system

[diddlydo]

But the water isn't at 45 degrees - it's scalding hot! Even in the summer with no heating on we only set it to 50 and we haven't contracted legionella in 40+ years in this house. Elf 'n'safety gone mad again.

[Ryzen]

diddly..if the stat is set at 50 and the water is scalding you may need at least 2 of the following
1...new cylinder stat
2...new diverter valve or actuator
3..new heating engineer