Heatmiser UH8 - 8 Zone 230v Wiring Centre Item Description: The Heatmiser UH8 is designed to work with our 4 channel 230v time clock (TM4) and 230v Set back thermostat (DS-SB) but equally could be used with any 230v room thermostat. Up to 8 zones can be controlled from the UH3. On board the UH8 are two heating time channels, each zone allows you to specify which time channel it should follow. 2 additional time channel connections are provided for hot water control or other auxiliary devices. On demand from any zone, a 230v output is provided to switch the relevant zone actuator, underfloor heating pump and valve. A volt free connection is supplied for the boiler, making it compatible with almost all types of boilers. A simple slide switch makes zone 8 suitable for controlling a radiator zone.