10
1. Purge gauge lines. Connect service gauge manifold
to base-valve service ports. Run system at least 10
minutes to allow pressure to stabilize.
2. Clamp a pipe clamp thermometer on the liquid line
near the liquid line service valve and 4-6" from the
compressor on the suction line.
a. Ensure the thermometer makes adequate contact
to obtain the best possible readings.
b. The temperature read with the thermometer
should be lower than the saturated condensing
temperature.
3. The dierence between the measured saturated
condensing temperature and the liquid line
temperature is the liquid Subcooling value.
4. TXV-based systems should have a Subcooling value
of 8°F +/- 1°F.
5. Add refrigerant to increase Subcooling and remove
refrigerant to decrease Subcooling.
Tonnage SH at Compressor
1.5 14°F +/- 1°F
2 11°F +/- 1°F
2.5 9°F +/- 1°F
3 9°F +/- 1°F
3.5 9°F +/- 1°F
4 9°F +/- 1°F
5 9°F +/- 1°F
1. Clamp a pipe clamp thermometer near the suction line
4-6” from the compressor on the suction line.
a. Ensure the thermometer makes adequate contact
for the best possible readings.
b. The temperature read with the thermometer
should be higher than the saturated suction
temperature.
2. The dierence between the measured saturated
suction temperature and the suction line temperature
is the Superheat value.
3. TXV-based systems should have a Superheat value
as shown in the table below.
4. Adjust Superheat by turning the TXV valve stem
clockwise to increase and counterclockwise to
.
a. If Subcooling and Superheat are low, the
TXV to the superheat setting specied in the table
below and then check Subcooling.
b. If Subcooling is low and Superheat is high,
charge to raise Subcooling to 8°F +/- 1°F then
check Superheat.
c. If Subcooling and Superheat are high, the
TXV valve to the superheat specied in the table
below then check the Subcooling value.
d. If Subcooling is high and Superheat is low,
the TXV valve to the superheat specied in the
table below and charge to lower the
Subcooling to 8°F +/- 1°F.
NOTE: DO NOT
Tonnage SH at Compressor
1.5 12°F +/- 1°F
2 12°F +/- 1°F
2.5 9°F +/- 1°F
3 9°F +/- 1°F
3.5 9°F +/- 1°F
4 9°F +/- 1°F
5 9°F +/- 1°F
To Next Page
Loading...
Need help?
General