Refrigerant Charging - Century B-VMH36SD-1 Service Manual

Procedure:
1) Confirm that both the 2-way and
3-way valves are set to the opened
position.
2) Connect the vacuum pump to 3-way
valve's service port.
3) Evacuate for approximately one hour.
Confirm that the compound meter
indicates <500 microns.
4) Close the valve (Low side) on the
charge set, turn off the vacuum pump,
and confirm that the gauge needle
does not move (approximately 5
minutes after turning off the vacuum
pump).
5) Disconnect the charge hose from the
vacuum pump.

2. Refrigerant charging

Service Manual - VMH 9/12/18/24 SU & VMH30/36S D Series
Procedure:
1) Connect the charge hose to the charging
cylinder, open the 2-way valve and the 3-
way valve. Connect the charge hose
which you disconnected from the vacuum
pump to the valve at the bottom of the
cylinder. Turn the cylinder bottom up to
ensure liquid charge.
2) Purge the air from the charge hose. Open
the valve at the bottom of the cylinder and
press the check valve on the charge set
to purge the air (be careful of the liquid
refrigerant).
3) Put the charging cylinder onto the
electronic scale and record the weight.
4) Open the valves (Low side) on the charge
set and charge the system with liquid
refrigerant. If the system cannot be
charged with the specified amount of
refrigerant, or can be charged with a little
at a time (approximately 5oz. each time),
while operating the air conditioner in the
cooling cycle, wait approximately one
minute and then repeat the procedure.
5) When the electronic scale displays the
proper weight, disconnect the charge
hose from the 3-way valve's service port
immediately. If the system has been
charged with liquid refrigerant while
operating the air conditioner, turn off the
air conditioner before disconnecting the
hose.
6) Mount the valve stem caps and the
service port. Use torque wrench to tighten
the service port cap to a torque of 13F.P.
Be sure to check for gas leakage.
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