Why does my hot water cool in my high-performance cylinder even when I am not using hot water?

Possible reasons your hot water is cooling include:

-Even though the cylinder has good insulation, some heat loss is inevitable over time if the heating source is not maintaining the temperature.

-The thermostat or immersion heater may not be calling for heat, meaning the cylinder isn’t being kept at the target temperature.

-If the system was undersized (the cylinder, coil or heat source), then it may struggle to maintain temperature when demand drops or when the heat source isn’t actively heating.

-The heating source may be set such that it heats to a certain temperature (e.g., around 60 °C) but then allows the cylinder to slowly cool when inactive.

Why is the water from my cylinder extremely hot?

If the water coming from your cylinder is extremely hot, this may be due to a fault with one of the thermostat devices. You should call your service engineer and ask them to inspect your product. 

Why is cold water flowing from my hot taps?

If cold water is flowing from your hot taps, this may indicate an issue with one of the programmers or a fault on the wider system, for example with the heat source itself. Please contact your service engineer and ask them to inspect your product.