Main components
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1.
Air purge valve
Remaining air in the water circuit will be automatically removed
via the air purge valve.
2.
Backup heater
The backup heater consists of an electrical heating element in
the backup heater vessel that will provide additional heating
capacity to the water circuit if the heating capacity of the outdoor
unit is insufficient due to low outdoor temperatures.
3.
Temperature sensors
Four temperature sensors determine the water and refrigerant
temperature at various points in the water circuit.
4.
Switch box
The switch box contains the main electronic and electrical parts
of the indoor unit.
5.
Heat exchanger
6.
Expansion vessel (10 l)
7.
User interface
The user interface allows the installer and user to set up, use
and maintain the unit.
8.
Refrigerant liquid connection
9.
Refrigerant gas connection
10. Shut-off valves (accessory)
The shut-off valves on the water inlet connection and water
outlet connection allow isolation of the indoor unit water circuit
side from the residential water circuit side. This facilitates
draining and filter replacement of the indoor unit.
11. Water inlet connection
12. Water outlet connection
RKHBH/X008BA
Indoor unit for air to water heat pump system
4PW54224-1A
13. Drain and fill valves
14. Water filter
The water filter removes dirt from the water to prevent damage
to the pump or blockage of the evaporator. The water filter must
be cleaned on a regular base. See "Maintenance and service"
1
on page 34.
15. Manometer
The manometer allows readout of the water pressure in the
water circuit.
16. Flow switch
2
The flow switch checks the flow in the water circuit and protects
the heat exchanger against freezing and the pump against
damage.
3
17. Pump
The pump circulates the water in the water circuit.
4
18. Backup heater thermal protector
The backup heater is equipped with a thermal protector. The
thermal protector is activated when the temperature becomes
5
too high.
6
19. Backup heater thermal fuse
The backup heater is equipped with a thermal fuse. The thermal
fuse is blown when the temperature becomes too high (higher
than the backup heater thermal protector temperature).
20. Pressure relief valve
The pressure relief valve prevents excessive water pressure in
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the water circuit by opening at 3 bar and discharging some
water.
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15
21. Pressure relief valve hose
The actual outlet of the pressure relief valve. Make sure to
provide a proper drain.
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Installation manual
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