Refrigerant Charging; Determining The Amount Of Charge - Wine Guardian SS025 Installation, Operation And Maintenance Manual

Fig. 1
24 volt two
position
terminal block
 The condensing unit needs to be hard-wired for the rated high voltage to be brought to
the field-installed contactor in enclosed plastic housing, from the load side (L1 & L2)
of the contactor. Run a ground lead to be connected to the condensing unit Ground
lead at the compressor. The load side of the field installed contactor will contain the
power leads that are found under the condensing unit's control box cover.
 Turn on power to the condensing unit 24 hours prior to system start-up to allow
crankcase heater to warm up compressor crankcase.

Refrigerant Charging

NOTE: The SS025, SS050, SS088 systems utilize a Headmaster control valve to
control head pressure at low ambient applications, therefore require a specific
initial charging procedure as outlined below. The SS200 system does not use this
method of low ambient control (utilizes fan cycling), but can accept initial charge
into the liquid receiver port the same way and the system has the same capacity.
Determining the amount of charge – When "refrigerant side" head pressure control is
utilized on a system, one of the most important factors is determining the total system refrigerant
charge. While on most packaged units the amount of charge is listed on the unit, the required
charge for a field built-up system cannot be listed by the manufacturer. Charge is usually added
when the system is started up until "proper" system performance is reached. However, this is not
satisfactory and if the system is to function properly year-round, the correct amount of extra
charge must be calculated ahead of time.
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Fig. 2
Com ports
On/Off
switch
24 volt
contactor
enclosure