Initial Start-Up At Low Outdoor Ambient Temperature; Pre-Operation Checks - HTW ECO-THERMAL PLUS -V18WD2RN8PLUS Manuel De L'utilisateur Et D'installation

Switch off the power supply before opening the switch box service panel and making any changes to the DIP switch
settings.
Operate the switches with an insulated stick (such as a closed ball-point pen) to avoid electrostaric damage to the
components.
1
DIP
ON=1 OFF=0
switch
1 Reserved Reserved
Reserved
2 Reserved
S1
0/0=Without IBH and AHS
1/0=With IBH
3/4
0/1=With AHS for heat mode
1/1=With AHS for heat mode
and DHW mode

10.3 Initial start-up at low outdoor ambient temperature

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 concrete floors cracking due to rapid temperature change. Please contact the responsible cast concrete building
contractor for further details.
To do so, the lowest water flow set temperature can be decreased to a value between 25°C and 35°C by adjusting the FOR
SERVICEMAN. Refer to "FOR SERVICEMAN/special function/preheating for floor" .

10.4 Pre-operation checks

Checks before initial start-up.
Switch off the power supply before making any connections.
After the installation of the unit, check the following before switching on the circuit breaker:
Field wiring：Make sure that the field wiring between the local supply panel and unit and valves (when applicable),
unit and room thermostat (when applicable), unit and domestic hot water tank, and unit and backup heater kit have
been connected according to the instructions described in the chapter 9.6 Field wiring, according to the wiring
diagrams and to local laws and regulations.
Fuses, circuit breakers, or protection devices Check that the fuses or the locally installed protection devices are of
the size and type specified in the chapter 14 Technical specifications. Make sure that no fuses or protection devices
have been bypassed.
Backup heater circuit breaker：Do not forget to turn on the backup heater circuit breaker in the switchbox (it
depends on the backup heater type). Refer to the wiring diagram.
Booster heater circuit breaker：Do not forget to turn on the booster heater circuit breaker (applies only to units with
optional domestic hot water tank installed).
Ground wiring：Make sure that the ground wires have been connected properly and that the ground terminals are
tightened.
Internal wiring：Visually check the switch box for loose connections or damaged electrical components.
Mounting：Check that the unit is properly mounted, to avoid abnormal noises and vibrations when starting up the
unit.
Damaged equipment：Check the inside of the unit for damaged components or squeezed pipes.
Refrigerant leak：Check the inside of the unit for refrigerant leakage. If there is a refrigerant leak, call your local
dealer.
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.
Air purge valve：Make sure the air purge valve is open (at least 2 turns).
Shut-off valves：Make sure that the shut-off valves are fully open.
WARNING
2 3 4 1 2 3 4
S1 S2
DIP
Factory
ON=1
switch
defaluts
Start pumpo after
OFF
1
six hours will
be invalid
OFF without TBH
2
S2
0/0=variable speed pump,
Max head: 8.5m
0/1=constant speed pump
OFF/OFF
3/4
1/0=variable speed pump,
Max head: 10.5m
1/1=variable speed pump,
Max head: 9.0m
DANGER
43
1 2 3 4
S4
DIP
Factory
OFF=0
switch
defaluts
Start pumpo after
Reserved Reserved
six hours will OFF 1
be valid
with TBH Reserved Reserved
OFF 2
S4
OFF/ON
3/4
Factory
ON=1 OFF=0
defaluts
OFF
OFF
Reserved OFF/OFF