Computherm Q4Z Operating Instructions Manual page 2

1. General description of the zone controller
As the boilers usually have only one connection point for
thermostats, a zone controller is needed in order to divide the
heating system into zones, to control the zone valves and to
control the boiler from more than one thermostat. The zone
controller receives switching signals from the thermostats,
controls the boiler and gives commands to open/close the heating
zone valves (max. 4 zones) associated with the thermostats.
It can control 1 to 4 heating zones, which are regulated by a
wired switch-operated thermostat. The zones can operate
independently from each other or, in case of need, all zones can
operate at the same time.
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