A cylinder thermostat controls the overall temperature of the hot water. It monitors the temperature of the water in the cylinder and turns the boiler off when the water temperature has reached the set point. If the hot water set point is reached but the heating is on, the boiler will not turn off. Instead the cylinder thermostat will close a valve so that no more hot water is provided. When some of the hot water is used the cylinder will be refilled with cold water and the cylinder thermostat allows the boiler to come back on until the set point is reached again. During hot water off periods set by the programmer, the boiler will not heat the water, even if requested by the cylinder thermostat.
An ideal temperature setting is between 60oC and 65oC, hot enough to kill off any harmful bacteria in the water while keeping energy costs down. These temperatures can cause scalding, so you should be careful with hot water straight out of the tap.
The following BEAMA Heating Controls members offer a range of heating controls:
Honeywell ACS Control Products
Pegler Yorkshire Group Limited
Secure Controls (UK) Ltd