Service
Section 6
6-12
Refrigerant Recovery/Evacuation and Recharging
PROCEDURES
Refrigerant Recovery/Evacuation
Do not purge refrigerant to the atmosphere. Capture
refrigerant using recovery equipment. Follow the
manufacturer’s recommendations.
Important
Manitowoc Ice, Inc. assumes no responsibility for
the use of contaminated refrigerant. Damage
resulting from the use of contaminated refrigerant
is the sole responsibility of the servicing
company.
Important
Replace the liquid line drier before evacuating
and recharging. Use only a Manitowoc (O.E.M.)
liquid line filter drier to prevent voiding the
warranty.
Connections
The QM series ice machines are critically charged.
There are no refrigerant access ports on QM series
ice machines.
1.
Locate the high and low side process tubes.
2.
Install a piercing valve (saddle valve) on both
the high and low side process tubes.
Important
Remove piercing valves after charging. Unit is
critically charged.
Important
Purge system with nitrogen while brazing to
prevent build up of copper oxide in the
refrigeration system.
Recovery/Evacuation
1.
Place the toggle switch in the OFF position.
2.
Install manifold gauges, charging scale, and
recovery unit or two-stage vacuum pump.
Recovery/Evacuation Connections
3.
Open the high and low side valves on manifold
gauges.
4.
Perform recovery or evacuation:
A.
Recovery: Operate the recovery unit as
directed by the manufacturer’s instructions.
B.
Evacuation prior to recharging: Pull the
system down to 250 microns. Then, allow
the pump to run for an additional half hour.
Turn off the pump and perform a standing
vacuum leak check.
NOTE: Check for leaks using a halide or electronic
leak detector after charging the ice machine.
5.
Follow the Charging Procedures on the next
page.
HIGH SIDE
PIERCING
VALVE
LOW SIDE
PIERCING
VALVE
OPEN
OPEN
MANIFOLD SET
OPEN
VACUUM PUMP/
RECOVERY UNIT
CHARGING
SCALE
SV1404A
Important
Manifold gauges must be removed properly to
ensure that no refrigerant contamination or loss
occurs. A quick disconnect is required for the
high side connection unless high side valve has
shut off.
