Rotex RKHBH008BA Installation Manual page 52

Field wiring configuration A
L
H Com
RKHB*/auto / Boiler
A
K1A K2A
N
Boiler Boiler thermostat input
thermostat input
A Auxiliary contact (normal closed)
H Heating demand room thermostat (optional)
K1A Auxiliary relay for activation of RKHB* unit (field
supply)
K2A Auxiliary relay for activation of boiler (field supply)
Field wiring configuration B
RKHB* RKHB*
X2M X2M
1 2 3 4 1 2 3 4
K1A K1A
H C C H
Com Com
RKRTR* RKRTW*
Boiler Boiler thermostat input
thermostat input
C Cooling demand room thermostat (optional)
H Heating demand room thermostat (optional)
Com Common room thermostat (optional)
K1A Auxiliary relay for activation of bolier unit
(field supply)
KCR Permission signal for the auxiliary boiler
Operation
■
Configuration A
When the room thermostat requests heating, either the RKHB*
unit or the boiler starts operating, depending on the position of
the auxiliary contact (A).
■
Configuration B
When the room thermostat requests heating, either the RKHB*
unit or the boiler starts operating, depending on the outdoor
temperature (status of "permission signal for the auxiliary
boiler").
When the permission is given towards the boiler, the space
heating operation by the RKHB* unit will be automatically
switched off.
For more details see field setting [C-02~C-04].
Installation manual
7
RKHB*
Boiler
thermostat input
X2M
1 2 3 4 X Y
K1A K2A
EKRP1HB
KCR
X1 X2
K1A
X Y
Boiler
thermostat input
■
NOTE Configuration A
Make sure that auxiliary contact (A) has sufficient
differential or time delay so as to avoid frequent
changeover between the RKHB* unit and the
boiler. If the auxiliary contact (A) is an outdoor
temperature thermostat, make sure to install the
thermostat in the shade, so that it is not
influenced or turned ON/OFF by the sun.
Configuration B
Make sure that the bivalent hysteresis [C-04] has
sufficient differential to avoid frequent changeover
between the RKHB* unit and the boiler. As the
outdoor temperature is measured via the outdoor
unit, air thermistor make sure to install the
outdoor unit in the shade, so that it is not
influenced by the sun.
Frequent switching may cause corrosion of the
boiler in an early stage. Contact the manufacturer
of the boiler.
■
During heating operation of the RKHB* unit, the
unit will operate so as to achieve the target
leaving water temperature as set on the user
interface. When weather dependent operation is
active, the water temperature is determined
automatically depending
temperature.
During heating operation of the boiler, the boiler
will operate so as to achieve the target leaving
water temperature as set on the boiler controller.
Never set the target leaving water temperature set
point on the boiler controller above 55°C.
■
Make sure to only have 1 expansion vessel in the
water circuit. An expansion vessel is already
premounted in the Rotex indoor unit.
NOTE Make sure to configure the DIP switch SS2-3 on the
PCB of the RKHB* switchbox correctly. Refer to "Room
thermostat installation configuration" on page 21.
For configuration B: Make sure to configure the field
settings [C-02, C-03 and C-04] correctly. Refer to
"Bivalent operation" on page 29.
CAUTION
Make sure that return water to the RKHB* heat exchanger
never exceeds 55°C.
For this reason, never put the target leaving water
temperature set point on the boiler controller above 55°C
(a)
and install an aquastat
the RKHB* unit.
Make sure that the non-return valves (field supply) are
correctly installed in the system.
Make sure that the room thermostat (th) is not frequently
turned ON/OFF.
Rotex shall not be held liable for any damage resulting
from failure to observe this rule.
(a) The aquastat valve must be set for 55°C and must operate to close the return
water flow to the unit when the measured temperature exceeds 55°C. When the
temperature drops to a lower level, the aquastat valve must operate to open the
return water flow to the RKHB* unit again.
Manual permission towards the RKHB* unit on the boiler.
In case only the RKHB* unit should operate in space
heating mode, disable the bivalent operation via setting
[C-02].
In case only the boiler should operate in space heating
mode, increase the bivalent ON temperature [C-03] to
25°C.
Indoor unit for air to water heat pump system
on the outdoor
valve in the return water flow of
RKHBH/X008BA
4PW54224-1A