
41
34
CHECKING REFRIGERANT CHARGE
Servicing of the refrigeration circuit must only be performed
by agencies or individuals possessing Type II or Universal
certification as defined in Section 608 of the Clean Air Act. See
Qualifications on page 8.
This HPWH unit is factory charged with 134a refrigerant. See the
rating label on the HPWH unit and Table 9 for refrigerant charge
by weight. It should not be necessary to add or remove refrigerant
during installation or start up. Refrigerant lost during frequent
refrigerant pressure testing can cause low refrigerant conditions.
Air and water flow should always be checked first to eliminate
other potential problems before checking the refrigerant charge.
Check Water Temperature Rise
Always check water temperature rise through the HPWH
unit’s internal heat exchanger before checking the refrigerant
charge. See Start Up on page 29 for information on how to
measure the water temperature rise.
If the measured water temperature rise during start up was
within 8°F to 12°F (4°C to 7°C) checking the charge is not
necessary unless other conditions warrant testing.
If the measured temperature rise through the HPWH unit is less
than 8°F (4°C) checking the charge is not necessary unless
other conditions warrant testing. Short water piping runs
between the HPWH and the storage tank will produce lower
temperature rises and are not problematic.
If the measured temperature rise through the HPWH unit is
more than 12°F (7°C) check for restrictions in the inlet and
outlet water piping connected between the HPWH unit and the
storage tank.
SUPERHEAT CALCULATION
1.
2.
Measure and record the suction pressure at the
suction line pressure access port inside the unit.
Convert the recorded suction pressure to
saturated temperature.
3. Measure the suction line temperature near the suction line
pressure access port inside the unit.
4. Compare the suction line temperature to the to the saturated
temperature in Table 10.
TABLE 10
R134A SATURATED TEMPERATURE CHART
SATURATED
TEMPERATURE °F
SATURATED
TEMPERATURE °C
REFRIGERANT
PRESSURE (PSI)
0
-18
7
5
-15
9
10
-12
12
15
-9
15
20
-7
18
25
-4
22
30
-1
26
35
2
30
40
4
35
45
7
40
50
10
45
55
13
51
60
16
57
65
18
64
70
21
71
75
24
79
80
27
87
85
29
95
90
32
104
95
35
114
100
38
124
105
41
135
110
43
146
115
46
158
120
49
171
125
52
185
130
54
199
135
57
214
140
60
229
145
63
246
150
66
263
155
68
281
34
5. The difference between saturated temperature and sucti
o
n
line temperature is the superheat
. Superheat normal range
should be 8°F to 12°F (4.4°C to 6.7°C).
TABLE 9
MODEL
FACTORY CHARGE R134A
C2
5
7
#
C60
C90
C125
C185
C250
14#
20#
60#
Содержание C125W
Страница 2: ......
Страница 5: ...5 PB ...
Страница 6: ...6 PB AI0 AI1 I I I I I I ...
Страница 7: ...7 PB ...