HWA1-A & HWA1-H
Air/Water chillers and heat pumps with axial fans
32
Models
HWA1-A/HWA1-H
0140
0147
0260
0272
0285
Output capacity of reference [kW]
40
47
60
73
85
The required minimum water flow rate [lt/s]
1,18
1,38
1,78
2,17
2,53
Recommended max water flow rate [lt/s]
2,35
2,76
3,57
4,33
5,06
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.
18.2
CHILLED WATER PRODUCTION (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 micro-processor control. In this case please
contact our company for the feasibility study and evaluation of changes to be made according to your needs. 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 in the start-up stages of the system.
18.3
HOT WATER PRODUCTION (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 which are not related to transitional or start-up stages may cause system’s failure with possible damages to compressor.
The maximum outlet water temperature should not exceed 55°C. At this temperature, the power consumption and performance
in terms of C.O.P. are enhanced if the outdoor air temperature is higher than 5°C, even if the unit is still able to work up to the
limit of -10°C with hot water production at 50°C.
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 operation of the unit, or the safety devices may act in critical situations.
The maximum power consumption will occur during the operation of the unit in chiller mode with outlet water temperature of
25°C and outdoor air temperature of 46°C.
18.4
AMBIENT TEMPERATURE OPERATING LIMITS AND RECAPITULATIVE TABLE
The units are designed and manufactured to operate in summer mode regime, with the condensate control and with outdoor air
temperatures included between -10°C and 46°C. In heating mode, the allowed range of the outdoor temperature goes from -15°C
to +40°C as a function of the water outlet temperature as indicated in the below table.
Operation limits
Min.
Max.
Water chiller mode
Ambient temperature
+10°C (-15°C*)
+46°C
Water outlet temperature
+5°C
+25°C
Heat pump mode and domestic hot water
Ambient temperature with domestic hot water at 50°C max.
-10°C
30°C (40°C**)
Ambient temperature with domestic hot water at 55°C max.
-7°C
+25°C (35°C**)
Water outlet temperature
+25°C(30°C***)
+55°C
* 0°C with fan motor of Y-Δ connection, -15°C with modulating fan motor.
** +40°C/+35°C, max air temperature for domestic hot water production at 50°C/55°C
only for bi-compressor units
.
*** +30°C, minimum water temperature for air temp. >30°C.
