TM 10-8145-222-23
0014
SERVICE CONTINUED
Pump Refrigeration Unit Down
Pumping the unit down can be accomplished to perform maintenance on the filter-drier (WP 0018), thermostatic
expansion valve (WP 0081), liquid line solenoid valve (WP 0047), CPR valve (WP 0062), or evaporator coil
(WP 0080). The majority of the refrigerant is pumped into the condenser coil and receiver as follows:
NOTE
The suction valve has a larger tube that connects to the accumulator and the
discharge valve has a smaller tube that connects to the condenser coil.
1. Close off service valves by turning compressor suction (Figure 1, Item 1) and discharge (Figure 1, Item 2)
service valves counterclockwise to backseat (open) them.
2. Attach manifold gauges (Figure 1, Item 3) to compressor suction (Figure 1, Item 1) and discharge (Figure 1,
Item 2) service valves.
3. Open (backseat) suction (Figure 1, Item 1) and discharge (Figure 1, Item 2) service valves two turns in
clockwise direction.
4. Purge gauge line by unscrewing the line from bottom of manifold gauges (Figure 1, Item 3).
0014-2