CAPÍTULO IV. DISCUSIÓN Y CONCLUSIONES
Ecuación 6: Ecuación del cálculo de la eficiencia total de distribución
The following steps are an example of how to choose the system units and indicates the way to decide on the model best suited to your own specific needs:
We recommend that you choose the AquaFREE system according to the heating load.
4.1.1. How to use the data in this chapter
Define the installation requirements: load, operating temperature and special installation needs. Then select the most suitable units. Decide on where to put the outdoor unit to allow easy maintenance and service.
Use the following information to calculate the most suitable units:
Relevant sections of Chapter 4:
Heating capacity curves: Section 4.2
Piping length and correction factors: Section 4.5 Noise-related data: Section 4.6
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In addition, use the following information from the technical catalogue:
General data: Chapter 2 Hydraulic circuit: Section 7.4
Setting and function of DIP switches for AquaFREE indoor units: Section 9.3 –
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4.1.2. Example of choosing units by heating load
We suggest the following method to determine the characteristics of the system units:
System requirements
Wet bulb temperature of the outside air inlet: -5 ºC
Temperature of the water outlet: 35 ºC
Temperature of the water inlet: 30 ºC
Thermal Load: 8.00 kW
Type of installation: Heating floor
Installation restrictions:
Power supply: 230 V, 1~, 50 Hz
AquaFREE module lower than the outdoor
unit: 15 m
Total equivalent distance between the
AquaFREE module and the outdoor unit: 20 m
Type of AquaFREE module:
AquaFREE RWM modules needed
Step 1:
NOTE:The calculation methods for thermal loads in the building should comply with the regulations applicable in each country.
Heating load:
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Capacities and selection data
4
Select the units
Select the units to make up the AquaFREE system according to the thermal load needed.
The system chosen should have a load capacity greater than the thermal load required by the installation.
Use section 4.2 to calculate your choice Unit chosen:
The total heating load is 8.00 kW, and the choice of system depends on the table of capacities (section 4.2) for heating floor (35/30ºC)
Heating floor
AquaFREE UNITS Outside air inlet temperature
WB (ºC)
Water outlet/inlet temperature (35/30ºC)
Max. CAP
RWM-4FSN1E
-6 9.20
-5 9.40
-3 9.30
Apply a correction factor according to the length and height of the piping (section 4.5) and the heating capacity given in Table 1:
The outdoor unit most suitable for your system requirements is:
Unit chosen RAS-4HVRNE/RWM-4FSN1E
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Step 2:
Table 1:Heating capacity data
NOTE:The defrosting factor is included in Table 1.
Heating capacity of the system (THA) = heating capacity (TH) x correction factor for
piping length (F) = 9.40 x 0.99 = 9.30 kW
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Capacities and selection data
Select units with electrical resistance
It is a geographical area where the 8.00 kW load is required at given moments.
Therefore, a 3 HP unit with supporting electrical resistance can be selected.
Wet bulb temperature of the outside air inlet: -5 ºC
Temperature of the water outlet: 35 ºC
Temperature of the water inlet: 30 ºC
Thermal load: 8.00 kW
Type of installation: Heating floor
Installation restrictions:
Power supply: 230 V, 1~, 50 Hz
AquaFREE module lower than the outdoor
unit: 15 m
Total equivalent distance between the
AquaFREE module and the outdoor unit: 20 m
Total heating load: 8.00 kW
The total heating load is 8.00 kW, and the choice of system depends on the table of capacities (section 4.2) for heating floor (35/30ºC)
Heating floor
AquaFREE UNITS Outside air inlet temperature
WB (ºC)
Water outlet/inlet temperature (35/30ºC)
As can be seen, the Total heating load > Capacity of the unit. These conditions require the use of additional electrical elements.
The capacity of the electrical elements required can be checked in Chapter 2 (General Data).
In the table and chapter 2 (General Data), select the unit with electrical resistance, which is model RWM-3FSN1E-6H1, with a total power of (6.70 x 0.98) + 4.50 kW of electrical resistance.
Unit with selected electrical
element. RWM-3FSN1E-6H1
Heating capacity data
NOTE:We advise using support heaters rather than overloading the selected unit.
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Capacities and selection data
4
Choice of units for installations with radiators or mixed installations (radiators + heating floor)
In the case of installations with radiators, use the same process as the heating floor method.
Choose the values in the table of water outlet/inlet temperature (45/40ºC) For mixed installations, use the graphs corresponding to the radiator installations.
4.1.3. Example of selecting cooling load
We suggest the following method to determine the characteristics of the system units:
System requirements
Dry bulb temperature for outside air inlet: 30 ºC
Temperature of the water outlet: 7 ºC
Temperature of the water inlet: 12 ºC
Thermal Load: 7.00 kW
Type of installation: Fan-coil
Installation restrictions:
Power supply: 230 V, 1~, 50 Hz
AquaFREE module lower than the outdoor unit: 15 m Total equivalent distance between the AquaFREE
module and the outdoor unit: 20 m
Type of AquaFREE module:
AquaFREE RWM modules needed –
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Step 4:
Step 1:Cooling load:
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Capacities and selection data
Select the units
Select the units to make up the AquaFREE system according to the thermal load needed.
The system chosen should have a load capacity greater than the thermal load required by the installation.
Use section 4.3 to calculate your choice Unit chosen:
The total cooling load is 7.00 kW, and the choice of system depends on the table of capacities (section 4.3) for fan-coil heating (7/12ºC)
Heating floor
AquaFREE UNITS Outside air inlet temperature
DB (ºC)
Water outlet/inlet temperature (7/12ºC)
Max. CAP
RWM-4FSN1E
25 9.40
30 8.70
35 8.20
Apply a correction factor according to the length and height of the piping (section 4.5) and the cooling capacity given in Table 1:
The outdoor unit most suitable for your system requirements is:
Unit chosen RAS-4HVRNE/RWM-4FSN1E
If you want to use heating floor for cold applications, please take the following points into account:
The water temperatures to be used for this type of installation vary between 19ºC and 21ºC depending on the ambient humidity.
The use of temperatures at 7ºC for this type of installation could cause condensation.
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Step 2:
Step 3:Cooling capacity of the system (TCA) = cooling capacity (TC) x correction factor for
piping length (F) = 8.70 x 0.96 = 8.35 kW
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Capacities and selection data