36
19.2
SSL
The super silenced unit (with SSL accessory) is provided not only with the thermo-acoustic shells on compressors but also with a
special diffuser installed on the fan. The diffuser structure improves the air flow efficiency and allows a fan speed reduction,
lowering the acoustic pressure by up to 7,2 dB(A) and energy consumption by up to 27% with unchanged airflow. That could lead
to a saving up of a lot of money in energy costs per fan per year. Alternatively, you could make use of the greater efficiency to
boost air performance by up to 9% with comparable energy consumption.
For more details about the power sound, you can see the technical data listed in paragraph
Errore. L'origine riferimento non è
stata trovata.
.
20
OPERATING LIMITS
20.1
EVAPORATOR WATER FLOW RATE
The nominal water flow rate is referred to a ∆T equal to 5°C, between the evaporator’s inlet a
nd outlet temperatures. The allowed
maximum flow rate is corresponding to ∆T=3°C. Higher values may produce too high pressure drops. The allowed minimum water
flow rate is corresponding to ∆T=8°C. Insufficient values
of water flow may produce too low evaporating temperatures according
to the operating status with the intervention of safety devices which would stop the unit and, in some particular cases, the water
can freeze in the evaporator coil which can breakdown the refrigeration circuit or causes the increasing of the condensing
pressure with the shutdown risk of the appliance and the compressor could be damaged.
We enclosed below a most accurate table showing the minimum water flow that should be ensured for the plate heat exchanger
in order to have the proper operation of unit as a function of the model (
note:
the water flow switch is used for preventing the
freezing sensor from failure in the case of insufficient water flow but it does not ensure the minimum flow rate required in order
the unit can work properly).
Models
i-HP
0125
0135
0250/0250F
0260
0270
Cooling capacity for reference [kW]
21,02
26,90
36,21
43,00
53,60
Minimum water flow rate that to ensure [L/s]
0,63
0,80
1,08
1,29
1,59
As a first approach, and in the absence of other detection systems, the proper flow rate for getting the best performance from
your unit can be found at maximum speed of the circulator, using the pressure gauges for controlling the pressure difference
between the return and the delivery water on the outside water connections of the unit and make sure that such value is equal or
less than the static pressure indicated on the curves shown in paragraph 15 for the respective models and if it’s necessary change
the settings (for the related circulator) that are reported in the control manual.
20.2
COLD WATER TEMPERATURE (SUMMER OPERATION)
The minimum temperature that is allowed at the evaporator’s outlet is 5°C: for lowest temperatures the unit should undergo
some necessaries structural modifications and different setting parameters of the controller with micro-processor. In this case
please contact our company for the feasibility study and evaluation of changes to be made according to your requests. The
maximum temperature that can be maintained at the outlet of the evaporator is 25°C. Higher temperatures (up to a maximum of
40°C) can anyway be tolerated during transitions and start-up phases of the system.
20.3
HOT WATER TEMPERATURE (WINTER OPERATION)
Once the system is working at the right temperature, the inlet hot water temperature should not be lower than 25°C; the lowest
values that are not related to transitional or start-up stages may cause system’s malfunction and possible compressor
breakdowns. The maximum outlet water temperature should not exceed 60°C. At this temperature, the power consumption and
performance in terms of C.O.P. are enhanced if the outdoor temperature is higher than 5°C, even if the unit is still able to work up
to the limit of -15°C (-25°C for versions with injection).
For higher temperatures than those pointed out, especially if have a concomitant with the reduction of the water flow rate, it may
cause abnormalities to the normal operating of the unit, or the safety devices act in critical cases.
The maximum power consumption of the heat pump alone will take place during the operation with outlet water temperature of
60°C and outdoor temperature of -15°C(-25°C for versions with injection)
in KW
1
2
1,5
2,5
-27%
in dB(A)
75
70
80
85
90
-7,2 dB(A)
AxiTop Diffuser
Less energy consumption at
constant air volume
Reduced noise at equal at
constant volume
