Honeywell DHC 23 Operating Instructions Manual page 5

DHC 23
Purpose
The DHC 23 is designed exclusively for regulating and controlling district heating
systems including domestic hot water heating which do not exceed a maximum flow
temperature of 120 °C.
Prerequisite for commissioning
1. The district heating system must be ready and filled with water so that the pumps
do not run dry.
2. The control device must be installed according to the installation instructions.
3. All electrical connections (power supply, valve actuators, pumps, sensor wiring, etc.)
must be made by the specialist according to the valid VDE regulations and
correspond to the corresponding circuit diagrams (see installation instructions).
4. If an underfloor heating system is connected, a limiting thermostat must be installed
by the customer in addition in the flow line after the heating circuit pump to switch
the pump off at too high flow temperatures.
If all these conditions are fulfilled (have them checked by the heating
specialist), the controller can be put into service.
The current time and date are already set in the factory and protected by a battery.
The timer works according to a basic program and the control functions are preset for
customary district heating systems.
SAFETY NOTES
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