Hoshizaki IM-240DME Service Manual page 77

7) Evacuation, Vacuum Pump and Refrigerant Charge [R404A] 7) Evacuation, Vacuum Pump and Refrigerant Charge [R404A]
Never allow the oil in the vacuum pump to flow backward. The vacuum level and vacuum Never allow the oil in the vacuum pump to flow backward. The vacuum level and vacuum
pump may be the same as those for the current refrigerants. However, the rubber hose and pump may be the same as those for the current refrigerants. However, the rubber hose and
gauge manifold to be used for evacuation and refrigerant charge should be exclusively for gauge manifold to be used for evacuation and refrigerant charge should be exclusively for
R404A. R404A.
8) Refrigerant Leak Check 8) Refrigerant Leak Check
Refrigerant leaks can be detected by charging the unit with a little refrigerant, raising the Refrigerant leaks can be detected by charging the unit with a little refrigerant, raising the
pressure with nitrogen and using an electronic detector. Do not use air or oxygen instead of pressure with nitrogen and using an electronic detector. Do not use air or oxygen instead of
nitrogen for this purpose, or rise in pressure as well as in temperature may cause R404A to nitrogen for this purpose, or rise in pressure as well as in temperature may cause R404A to
suddenly react with oxygen and explode. Be sure to use nitrogen to prevent explosion. suddenly react with oxygen and explode. Be sure to use nitrogen to prevent explosion.
[b] REFRIGERANT RECOVERY [b] REFRIGERANT RECOVERY
The refrigerant must be recovered if required by an applicable law. A Low-side Access The refrigerant must be recovered if required by an applicable law. A Low-side Access
Valve is provided on an extension pipe connected to the suction port of the Compressor. Valve is provided on an extension pipe connected to the suction port of the Compressor.
On the DME/XME and DWME/XWME, a Tap Valve should initially be fitted to the High-side On the DME/XME and DWME/XWME, a Tap Valve should initially be fitted to the High-side
Process Tube to be replaced with a proper Access Valve (see Fig. 45) when recovery is Process Tube to be replaced with a proper Access Valve (see Fig. 45) when recovery is
completed. completed.
The DSME/XSME high side can be accessed using the Gauge Port on the Upper Condenser The DSME/XSME high side can be accessed using the Gauge Port on the Upper Condenser
Line Access Valve (liquid return) attached to the right side of the icemaker. Line Access Valve (liquid return) attached to the right side of the icemaker.
Recover the refrigerant, and store it in a proper container. Do not discharge the refrigerant Recover the refrigerant, and store it in a proper container. Do not discharge the refrigerant
into the atmosphere. into the atmosphere.
[c] EVACUATION AND RECHARGE [c] EVACUATION AND RECHARGE
1) On the DME/XME and DWME/XWME, attach Charging Hoses, Service Manifold and 1) On the DME/XME and DWME/XWME, attach Charging Hoses, Service Manifold and
Vacuum Pump to the Low-side and High-side (to be fitted by servicer) Access Valves. Vacuum Pump to the Low-side and High-side (to be fitted by servicer) Access Valves.
Connect the DSME/XSME Charging Hoses as described in "[b] REFRIGERANT Connect the DSME/XSME Charging Hoses as described in "[b] REFRIGERANT
RECOVERY". If possible, use Quick Release Connectors onto the Access Valves RECOVERY". If possible, use Quick Release Connectors onto the Access Valves
(especially on the high side). (especially on the high side).
2) Turn on the Vacuum Pump. 2) Turn on the Vacuum Pump.
3) Allow the Vacuum Pump to pull down to a 760 mmHg vacuum. Evacuating period depends 3) Allow the Vacuum Pump to pull down to a 760 mmHg vacuum. Evacuating period depends
on the pump capacity. on the pump capacity.
4) Close the Low-side and High-side Valves on the Service Manifold. 4) Close the Low-side and High-side Valves on the Service Manifold.
5) Disconnect the Vacuum Pump, and attach a Refrigerant Charging Cylinder to accurately 5) Disconnect the Vacuum Pump, and attach a Refrigerant Charging Cylinder to accurately
weigh in the liquid charge. Remember to purge any air from the Charging Hose. See the weigh in the liquid charge. Remember to purge any air from the Charging Hose. See the
Nameplate for the required refrigerant charge. Nameplate for the required refrigerant charge.
E1CG4880210 E1CG4880210
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