Finish Charging Procedures; Preliminary; Remote "M-Series; Built-Up Remote "B-Series" Condensing Units - Standex Master-Bilt B-SERIES Installation & Operation Manual

FINISH CHARGING PROCEDURES

A. Preliminary
1. Be sure all service valves are "open".
2. Loose the compressor hold-down bolts and remove shipping clips to allow compressor to float freely
on the springs.
3. Check evaporator fan motors after start-up. Medium temperature, air defrosts fans run continuously.
Low temperature fans and coolers provided with electric defrost will be delayed by the fan control.
4. Start the system by "flipping on" the circuit breaker in the unit electric box.
Start charging per (B), (C), (D) or (E) on the following pages.
5.
CAUTION: Never add liquid refrigerant to the suction side of the compressor.
Check operating pressures while charging and on initial pull down to prevent damage if a
6.
problem occurs. If system "floods" back to the compressor, adjust the thermostatic expansion
valve as required for proper operation. There should be at least +30°F superheat entering the
compressor.
Observe compressor amperage draw and compare to compressor nameplate to prevent damage
7.
due to high amperage. The oil sight glass should be between 1/2 and 3/4 full during normal
operation
Remote "M-Series" Condensing Units
B.
1. For models without head pressure control valve: With the system operating, add refrigerant
until the sight glass indicates a full charge, then add one pound for each 2 rated horsepower of
the condensing unit when charging above +75°F. If ambient is below +75°F, add 1/2 to the
above.
2. For models with head pressure control valve: Add additional charge per the procedure.

Built-Up Remote "B-Series" Condensing Units

C.
These units are equipped with a head pressure control valve for low ambient operation. This valve
will flood the condenser when ambient temperatures are low, requiring additional refrigerant to
provide correct operation under various ambient conditions. See attached Charts B and C (pages 19
and 20) for the additional charge data, and finish charging as follows.
1. Add the proper refrigerant for a full sight glass.
2. Add additional charge per the procedure on page 19.
DANGER
Charging of the refrigeration system must be performed only by a certified refrigeration
mechanic. Improper or faulty hook-up of refrigeration electrical components can result in injury
or death.
5/16 Rev. B 57-02497 13