[B] Refrigerant Recovery; [C] Evacuation And Recharge - Hoshizaki DCM-60KE Service Manual

8) Refrigerant Leak Check
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
nitrogen for this purpose, or rise in pressure as well as in temperature may cause R134A to
suddenly react with oxygen and explode. Be sure to use nitrogen to prevent explosion.

[b] REFRIGERANT RECOVERY

The refrigerant must be recovered if required by an applicable law. Recover the refrigerant
from the access valve, and store it in a proper container. Do not discharge the refrigerant
into the atmosphere.
When replacing the drier, take the opportunity to also fit a low-side access valve and a
high-side access valve for ease of charging liquid refrigerant.

[c] EVACUATION AND RECHARGE

1) Attach a charging hose of a gauge manifold to a vacuum pump and the low-side access
valve (to be fitted by service personnel).
2) Open the low-side valve on the gauge manifold, and turn on the vacuum pump.
3) Allow the vacuum pump to pull down to a 760 mmHg vacuum. Evacuating period
depends on the pump capacity.
4) Close the low-side valve on the gauge manifold.
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
nameplate for the required refrigerant charge.
6) Open the low-side valve on the gauge manifold and the valve on the charging cylinder.
7) When no more refrigerant is drawn in, turn on the ice dispenser. When the required
amount of refrigerant has been charged, close the valve on the charging cylinder and
turn off the ice dispenser.
8) Close the low-side valve on the gauge manifold.
9) Disconnect the charging hose from the access valve. Always cap the access valve to
prevent a refrigerant leak.
10) Always thoroughly leak test all joints and valve caps.
11) Avoid charging large quantities of liquid into the low side in case of damage to the
compressor.
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