25
NRL 028-075 60Hz
EN
12. TOTAL RECOVERY
Average water temperature °C/°F 30/86 40/104 50/122
Multiplicative co-efficients
1,04 1,02
1
12.1. PRESSURE DROPS
The NRL models with total recovery always have
1 recuperator.
The features of the recuperators and the pressure
drop curves are given below; filter losses are not
considered.
The pressure drops in the diagram are relative to
an average temperature of 50°C / 122°F.
Shows the corrections to apply to pressure drops
on variation of the average water temperature.
In the case of functioning with total heat recovery,
machine performance does not depend on the
external air temperature, but on that of the hot
water produced: the electric input power and
the recovery heating capacity are obtained by
multiplying the values (Pa, Pr) by the respective
corrective co-efficients (Ca, Cr), deductible from
the following diagrams.
The temperature of the hot water produced is
given in correspondence with each curve, to
which reference is made, assuming a difference
of 5°C/41°F between inlet and outlet from the
total recuperator.
The cooling capacity (Pf) is obtained from the
distance between the recovery heating capacity
(Pr) and input power (Pa).
Nominal value referring to:
Air temperature
35°C / 95°F
Water at the desuperheater
50°C / 122°F
∆t
5°C / 41°F
Units with Total Recovery (T) do not envision the fol-
lowing versions:
YT
XT (only for temperature under 4°C/39,2°F)
35°C / 95°F
40°C / 104°F
45°C / 113°F
50°C / 122°F
55°C / 131°F
5
0,9
1,0
1,1
1,2
1,3
1,4
1,5
6
7
8
9
10
11
12
13
14
15
16
17
18
°C
64,4
°F
41
41
43
45
47
49
51
53
55
57
59
61
63
Temperature of the water produced
RECOVERED HEATING CAPACITY CORRECTIVE CO-EFFICIENTS
Cr
35°C / 95°F
40°C / 104°F
45°C / 113°F
50°C / 122°F
55°C / 131°F
5
0,7
0,8
0,9
1,0
1,1
1,2
6
7
8
9
10
11
12
13
14
15
16
17
18
64,4
°F
°C
41
41
43
45
47
49
51
53
55
57
59
61
63
INPUT POWER WITH RECOVERY CORRECTIVE CO-EFFICIENTS
Ca
Temperature of the water produced
TOTAL RECOVERY PRESSURE DROPS
Pr
essur
e dr
op
Water flow rate
0
50
100
150
200
250
kPa
10000
20000
30000
40000
50000
60000
l/h
gpm
264
0
40
80
120
160
200
240
0
10
20
30
40
44
psi
1
2
3
4
5
1
0280-0300-0330
2
0350-0500-0550-0600
3
0650
4
0700
5
0750
Pressure drop corrections on variation of the
average water temperature.