Ferroli 150.4 Technical Manual page 19

1) The Standard Performances tables in the Technical data and standard performances chapter give the
Useful output capacity in the cooling mode and Heating output in the heating mode values with the relative com-
pressor input power values of each unit in standard conditions. The data can be interpolated but not extrapola-
ted.
2) The Technical data and standard performances tables in this technical handbook refer to use of R407C refri-
gerant, as shown by the titles in the reference section and depending on the unit in question.
3) The tables under the Standard Performances values give the operating temperature limits of the outdoor air
that may enter the coils.
4) The power input values in the Standard Performances tables refer to the compressors alone. Consult the
Technical data of the unit tables for the power input of the fans at their top rate.
5) The Standard Performances values refer to 5 C of ΔT of the water between the inlet and outlet of the plate-
type heat exchanger. Use correction values F
cooling mode. Corrective factor F
re the plate type heat exchanger operates in the correct way, comply with the limits to use given in the Loss of
head and Useful head sections.
6) The Standard performances values are based on a 0.44* x10
on the wet side. Use correction factor F
7) The Standard Performances values refer to a unit installed in places at zero meters above sea level (Pb =
1013 mbar). Use Performances correction factor F
8) The Standard Performances values in the case of operation in the heating mode refer to outdoor air with 87%
relative humidity. Use correction factor FcUr in tab. 4 for different values.
9) Consult the Loss of head section to determine the loss of head on the wet side through the heat exchanger. If
the units are equipped with the Pumping Module accessory with storage on the water supply plant delivery, the
useful head of the unit can be determined by means of the diagram in the Useful head section. Remember that
the curves refer to the useful head calculated as difference between the pump head and the loss of head of the
components (filter, on-off devices, pipes, tank, plate type heat exchanger) installed in the hydraulic circuit of the
unit.
10)Use the Noise levels tables to check the acoustics.
11)If the version with the Pumping Module accessory is being evaluated (standard type with storage on the delivery
or storage pre-engineered for the primary or secondary circuit), check the capacity of the surge chamber in the
system in the Maximum water volume section.
Example of how the unit is selected:
The unit must be able to supply an 160 kW capacity in the following conditions:
- Outdoor air temperature = 40 C
- Temperature of the cold water outlet by the machine = 6 C
- Inlet/outlet temperature difference of the water Δt = 5 C
- The unit must also be able to provide a 200 kW heating output, working in the following conditions:
- Outdoor air temperature = 5 C
- Relative humidity of the outdoor air = 70%
- Temperature of the hot water outlet by the machine = 50 C
- Inlet/outlet temperature difference of the water Δt = 5 C
Also consider:
- a 0.88x10-4m C/W fouling factor on the wet side of the heat exchanger
2
- unit installed in a place at 900 meters a.s.l.
Solution:
The reversible refrigerating power must first be chosen by selecting the machine that meets the required values
in the cooling mode and by then checking that the machine selected is able to provide the power required in the
heating mode.
Selection for operation in the cooling mode:
In view of the operating specifications required, a basic version of the unit can be chosen as there are no parti-
cular limitations concerning acoustic emission.
HOW TO SELECT THE UNIT
given in Tab.3 for different values, in the case of operation in the
cD
is not considered in the heating mode as its influence is negligible. To ensu-
cD
indicated in Tab. 1 for different values.
cP
indicated in Tab. 2 for operation at different altitudes.
cH
m C / W fouling factor of the heat exchanger
-4 2
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