Hitachi RWM-(H)FSN3E Technical Catalogue page 70

4 Capacity and selection
data
Procedure description
The selection procedure given in this chapter is a simple example structured into 3 main blocks:
First, a) once the energy system to be used has been chosen (Mono-energy for this example), the YUTAKI S system will
be selected depending on the required regular heating load. Next, b) It will be check that the combination (YUTAKI S +
electric heater) covers the temporary needs of the coldest days of the year. Finally, c) it will be selected the Domestic Hot
Water Tank accessory.
a) Selection for a required regular heating load
• Step 1: Initial pre-selection
These conditions will determine the entry in the Maximum heating capacity tables, see section
tables, where we can identify which unit has heating capacity to cover the required regular heating load by the installation
(9.0 kW for an inlet/outlet water temperature of 30/35 ºC and an ambient temperature of -5ºC WB).
RAS-4HVRNME-AF + RWM-4.0(H)FSN3E

RAS-10HRNME-AF + RWM-10.0(H)FSN3E
As can be seen in the table, the YUTAKI S system that covers the installation's heating requirements is the combination of
RAS-4HVRNME-AF + RWM-4.0FSN3E. Therefore, this will be the pre-selected YUTAKI S system.
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TCGB0070 rev.3 - 04/2012
Proposed energy system
Inlet/outlet water temperature
Regular ambient temperature WB/DB
(HR = 85%)
Required regular heating load
Ambient temperature WB/DB on the coldest
day of the year (HR = 85%)
Heating load required on the coldest day of
the year
Installation restrictions
Installation type
Power supply
Indoor unit lower than outdoor unit
Equivalent piping length between outdoor
and indoor unit
12.0 kW, -15 ºC WB
9.0 kW, -5 ºC WB
YUTAKI S system
RAS-2HVRN2 + RWM-2.0(H)FSN3E
RAS-3HVRNME-AF + RWM-3.0(H)FSN3E
RAS-5HVRNME-AF + RWM-5.0(H)FSN3E
RAS-6HVRNME-AF + RWM-6.0(H)FSN3E
RAS-8HRNME-AF + RWM-8.0(H)FSN3E
Mono-energy
30/35 ºC
-5/-4 °C
9.0 kW
-15/-14.5 ºC
12.0 kW
Radiant floor
1~ 230V 50Hz
15 m
20 m
Capacity of
YUTAKI S
system
Heating load
demanded
Hours
Maximum heating capacity (kW)
5.7
8.9
11.2
13.3
13.9
20.2
24.8
Maximum heating capacity