15
Subcooling = Saturated Line Temperature - Liquid Line Temperature
Single Speed Application—WPC45
1.
Purge the gauge lines.
2.
Connect the service gauge manifold to the access fittings.
Run the system for at least 10 minutes to allow the pressure
to stabilize.
3.
Temporarily install a thermometer on the liquid (small) line
near the liquid line access fitting with adequate contact and
insulate for best possible reading.
4.
Check subcooling and superheat. Systems with TXV
application should have a subcooling of 10 + 2°F and
superheat of 15ºF to 18ºF.
a)
If subcooling and superheat are low, adjust TXV to 15ºF to
18ºF, and then check subcooling.
b)
If subcooling is low and superheat is high, add charge to
raise subcooling to 10ºF ± 2ºF then check superheat.
c)
If subcooling and superheat are high, adjust TXV valve to
15ºF to 18ºF, and then check subcooling.
d)
If subcooling is high and superheat is low, adjust TXV
valve to 15ºG to 18ºF superheat and remove charge to
lower the subcooling to 10ºF ± 2ºF.
NOTES:
■
The TXV should not be adjusted at light load conditions of
55ºF (13ºC) to 60ºF (16ºC). Under such conditions, only the
subcooling can be evaluated. This is because the suction
pressure is dependent upon the indoor airflow and the wet
bulb temperature.
■
Do not adjust the charge based on the suction pressure
unless there is a gross undercharge.
5.
Disconnect the manifold set. Installation is complete.
2-Speed Application—WGPH45
Run the unit on low-stage cooling for 10 minutes until the
refrigerant pressures stabilize. Follow the guidelines and methods
below to check the unit operation and ensure that the refrigerant
charge is within limits. Charge the unit on low stage.
1.
Purge the gauge lines.
2.
Connect the service gauge manifold to the access fittings.
Run the system for at least 10 minutes to allow the pressure
to stabilize.
3.
Temporarily install a thermometer on the liquid (small) line
near the liquid line access fitting with adequate contact and
insulate for best possible reading.
4.
Check subcooling and superheat. The 2-stage systems
running on low stage with TXV application should have a
subcooling of 5ºF to 7ºF and superheat of 15ºF to 18ºF.
a)
If subcooling and superheat are low, adjust TXV to 15ºF to
18ºF superheat, then check subcooling.
NOTE:
To adjust superheat, turn the valve stem clockwise
to increase and counterclockwise to decrease.
b)
If subcooling is low and superheat is high, add charge to
raise subcooling to 5ºF to 7ºF, and then check superheat.
c)
If subcooling and superheat are high, adjust TXV valve to
15ºF to 18ºF superheat, and then check subcooling.
d)
If subcooling is high and superheat is low, adjust TXV
valve to 15ºF to 18ºF superheat and remove charge to
lower the subcooling to 5ºF to 7ºF.
NOTE:
Do not adjust the charge based on the suction
pressure unless there is a gross undercharge.
5.
Disconnect the manifold set. Installation is complete.
70
15 150
53
72
16
160
56
74
17 170
60
76
19
Saturated Liquid Pressure Temperature
Liquid Pressure
Saturated Liquid Temperature ºF
Liquid Pressure
Saturated Liquid Temperature ºF
PSIG
R-410A
PSIG
R-410A
200
70 375
112
210
73 405
118
220
76 415
119
225
78 425
121
235
80 435
123
245
83 445
125
255
85 475
130
265
88 500
134
275
90 525
138
285
92 550
142
295
95 575
145
305
97 600
149
325
101 625
152
355
108
Saturated Suction Pressure Temperature
Suction Pressure
Saturated Suction Temperature ºF
Suction Pressure
Saturated Suction Temperature ºF
PSIG
R-410A
PSIG
R-410A
