Refrigerant Recovery, Evacuation, And Recharge - Mlh Model (Low Side, Parallel Rack System) - Hoshizaki FD-1001MLH(-C) Service Manual

5) Disconnect the gauge manifold hose from the vacuum pump and attach it to a
refrigerant service cylinder. Remember to loosen the connection and purge the air from
the hose. For air-cooled and water-cooled models, see the nameplate for the required
refrigerant charge. For remote air-cooled models, see the rating label inside the
icemaker. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which
meets ARI Standard 700 (latest edition) be used.
6) A liquid charge is recommended for charging an R-404A system. Invert the service
cylinder and place it on scales. Open the high-side valve on the gauge manifold.
7) Allow the system to charge with liquid until the proper charge weight is met.
8) If necessary, add any remaining charge to the system through the low-side. Use a
throttling valve or liquid dispensing device to add the remaining liquid charge through
the low-side access port with the unit running.
9) Close the gauge manifold valves and disconnect the gauge manifold hoses.
10) Cap the access valves to prevent a possible leak.
4. Refrigerant Recovery, Evacuation, and Recharge - MLH Model (low side, parallel rack
system)
a) Refrigerant Recovery
Using proper refrigerant practices, close the liquid and suction line service valves at the
rack system. Then, follow the steps below to recover the refrigerant from the line set and
icemaker and store it in an approved container. Do not discharge the refrigerant into the
atmosphere.
1) Turn off the icemaker power supply.
2) Close the liquid and suction line service valves at the rack system.
3) Connect gauge manifold hoses to the line set liquid and suction access valves.
4) Place magnets on top of the liquid and suction line solenoids.
5) Recover the refrigerant from the line set and icemaker. Note the charge amount
removed. Do not discharge the refrigerant into the atmosphere.
b) Brazing
See "V.A.2. Brazing."
c) Evacuation and Recharge (R-404A)
1) Attach a vacuum pump to the system. Be sure to connect charging hoses to both liquid
and suction access valves.
The vacuum level and vacuum pump may be the same as those for current
refrigerants. However, the rubber hose and gauge manifold to be used for
evacuation and refrigerant charge should be exclusively for POE oils.
2) Turn on the vacuum pump. Never allow the oil in the vacuum pump to flow backwards.
3) Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends
on pump capacity.
IMPORTANT
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