gForce Ultra IOM
60
Finish charging by slowly opening the valve on the refrigerant manifold set to meter liquid refrigerant
into the low side of the system, with the compressor operating at maximum speed, make sure to obtain
the required sub-cooling and verify superheat shown in the table below. Use a liquid charging adapter
to prevent liquid refrigerant from entering the compressor. The unit should be allowed to stabilize for
15 to 20 minutes to verify key measurements.
8 to 15°F (-13.33 to -9.44°C)
Differential Temperature - Depending on ambient conditions,
at compressor’s maximum speed
Measure the superheat at the compressor suction line at least 6 inches (152 mm) away from the
compressor. Compare suction pressure and temperature reading between the dap4 and the manifolds.
If the difference between the manifold reading and dap4 reading is more than 5%, check for the EEV
wiring and any possible alarms on dap4, or EEV driver. Measure sub-cooling at the liquid line.
When charging is complete, add the correct amount of oil. This procedure must be conducted with the
system running at high load (compressor at full speed).
5.8.2. Additional Oil
When charging is complete, add the correct amount of oil to each circuit. In installations with good oil
return and line runs up to 50 ft (15 m), no additional oil is required. If installation lines exceed 50 ft (15
m), additional oil needs to be added. Add 1 or 2% of the total system refrigerant charge (in weight) can
be used to roughly define the required oil top-up quantity.
Top-up the oil while the compressor is idle. Use any accessible connector on the compressor suction
line and a suitable pump. ALWAYS use clean original Danfoss POE oil 160SZ or equivalent from new
cans.
After charging, verifying sub-cooling and oil level.
Close the valve on the refrigerant manifold gauge set and close the service valve on the refrigerant
tank and disconnect the refrigerant manifold gauge set.