Initial Start-Up At Low Outdoor Ambient Temperatures; Pre-Operation Checks; Checks Before Initial Start-Up; Powering Up The Indoor Unit - Rotex RKHBH008BB3V3 Manuel D'installation

8.5. Initial start-up at low outdoor ambient
temperatures
During initial start-up and when water temperature is low, it is
important that the water is heated gradually. Failure to do so may
result in cracking of concrete floors due to rapid temperature change.
Please contact the responsible cast concrete building contractor for
further details.
To do so, the lowest leaving water set temperature can be decreased
to a value between 15°C and 25°C by adjusting the field setting
[9-01] (heating set point lower limit). Refer to "8.9. Field settings" on
page 26.
INFORMATION
If leaving water temperature is set between 15°C and
25°C, heating is performed by the backup heater only.
INFORMATION
The function underfloor heating screed dry-out program
offers the possibility to execute automatically the gradual
heat up. See "9.3. Underfloor heating screed dry-out
program" on page 42.

8.6. Pre-operation checks

Checks before initial start-up

DANGER
Switch off all relevant power supply before making any
connections.
After the installation of the unit, check the following before switching
on the circuit breaker:
1 Installation
Check that the unit is properly installed to avoid abnormal noises
and vibrations when starting the unit.
2 Field wiring
Make sure that the field wiring between local supply panel and
indoor unit, outdoor unit and indoor unit, indoor unit and valves
(when applicable), indoor unit and room thermostat (when
applicable), and indoor unit and domestic hot water tank has
been carried out according to the instructions described in the
chapter "7. Electrical wiring work" on page 17, according to the
wiring diagrams and according to the applicable legislation.
3 Fuses or protection devices
Check that the fuses or the locally installed protection devices
are of the size and type specified in the chapter "12. Technical
specifications" on page 49. Make sure that neither a fuse nor a
protection device has been bypassed.
4 Backup heater circuit breaker F1B/F3B
Do not forget to turn on the backup heater circuit breaker F2B in
the switch box (F1B/F3B depends on the backup heater type).
Refer to the wiring diagram.
5 Booster heater circuit breaker F2B
Do not forget to turn on the booster heater circuit breaker F2B in
the switch box (applies only to units with optional domestic hot
water tank).
6 Earth wiring
Make sure that the earth wires have been connected properly
and that the earth terminals are tightened.
7 Internal wiring
Visually check the switch box on loose connections or damaged
electrical components.
(1) Only applicable for tank with built-in electrical booster heater (RKHW*).
Installation manual
25
(1)
8 Fixation
Check that the unit is properly fixed, to avoid abnormal noises
and vibrations when starting up the unit.
9 Damaged equipment
Check the inside of the unit on damaged components or
squeezed pipes.
10 Refrigerant leak
Check the inside of the unit on refrigerant leakage. If there is a
refrigerant leak, call your local dealer.
11 Power supply voltage
Check the power supply voltage on the local supply panel. The
voltage must correspond to the voltage on the identification label
of the unit.
12 Pipe size and pipe insulation
Be sure that correct pipe sizes are installed and that the
insulation work is properly executed.
13 Stop valves
Make sure that the stop valves on the outdoor unit (gas and
liquid) are fully open.
14 Air purge valve
Make sure the air purge valve is open (at least 2 turns).
15 Pressure relief valve
Check if the backup heater is completely filled with water by
operating the pressure relief valve. It should purge water instead
of air.
NOTICE
Operating the system with the backup heater not
completely filled with water will damage the backup
heater!
16 Water leak
Check the inside of the unit on water leakage. in case there is a
water leakage close the water inlet and water outlet shut-off
valves and call your local dealer.
17 Shut-off valves
Make sure that the shut-off valves are correctly installed and
fully open.
NOTICE
Operating the system with closed valves will damage
the pump!

8.7. Powering up the indoor unit

When power supply to the indoor unit is turned on, "88" is displayed
on the user interface during its initialisation, which might take up to
30 seconds. During this process the user interface cannot be
operated.
Indoor unit for air to water heat pump system
RKHBH/X008BB
4PW62574-1 – 10.2010