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Monobloc Outdoor Unit Installation Manual
10.11 Coil heating control for compressor:
CAUTION:
When the unit doesn’t operate, the compressor can be energized. The coil heating control has the
function of heating the compressor by applying a current to the compressor when not operating instead
of using a case heater.
This control is for the purpose of preventing stagnation of the refrigerant inside the compressor.
10.12 Defrost cycle:
When the outdoor air temperature is low and the ambient humidity is high, the probability of frost forming on the
surface of the outdoor coil increases. The frost covering the outdoor coil may reduce the air flow across the coil
and impair the performance of the unit. To remove the frost from the coil, the control initiates the defrost cycle
when necessary.
During the defrost cycle, the refrigerant circuit is forced into the cooling mode. To prevent the water loop from
cooling down, BPHE and piping electric heaters may be started.
CAUTION:
Please note that “defrost” and “home anti-freeze protection” are two different modes. Defrost is used
in order to remove the frost that is covering the outside coil, whereas the home anti-freeze protection is
used to maintain the minimum room temperature.
10.13 Night mode capacity control:
The night period is defined by the start hour and the end hour which can be set by the user. The night mode
allows users to configure the unit to operate with specific parameters within a given period of time, e.g. night
period. Particularly this mode permits the reduction of compressor frequency (and noise level) during defined
period.
10.14 Drying mode:
The Drying mode enables a gradual water temperature ramp-up in Heat mode for UFH drying. This operating
mode can only be selected from the service access level, it is automatically stopped at the end of the configured
period.
The following parameters need to be set to operate in drying mode:
•
Drying Starting Setpoint [P595]
•
Drying Warm-up days [P596]
•
Drying Ramp-up days [P597]
•
Drying Hold-up days [P598]
•
Heating Home Water Setpoint [P401]
10.15 Summer mode:
The RUA-CP**01H units may operate in Summer mode which is active under the following conditions:
•
when the Summer Switch is closed
•
or when conditions on OAT [P716] and time [P717] and [P718] are validated (see section 8.2)
When the Summer mode is active, then the unit may operate only as specified below.
Cooling Mode
Heating Mode
DHW Mode
P
X
P
