Page
10
Air Evacuation
9
Preparations and Precautions
can cause abnormal rises in pressure, which
can damage the air conditioner, reduce its
efficiency, and cause injury. Use a vacuum pump
and manifold gauge to evacuate the line set and the
indoor unit, removing any non-condensable gas
and moisture from the system.
Evacuation should be performed upon initial
installation, and when unit is relocated.
BEFORE PERFORMING EVACUATION
Check to make sure that both LIQUID
SIDE and GAS SIDE pipes between
the indoor and outdoor units are
connected properly, in accordance with the
Refrigerant Piping Connection section of
this manual.
Check to make sure all wiring is connected
properly.
Evacuation Instructions
Before using the manifold gauge and vacuum
pump, read their operation manuals to familiarize
yourself with how to use them properly.
Manifold Gauge
Low pressure gauge
-76cmHg
Low Pressure Valve
High Pressure
Valve
Blue (low) Hose
Yellow (middle) Hose
Vacuum
Pump
High Pressure Gauge
Outdoor Unit Service Valve Set (GAS and LIQUID Valves)
1.
Connect the blue (low side) hose of the manifold
gauge to the service port on the outdoor unit’s
GAS SIDE valve (use a 1/4” to 5/16” port adapter if
needed, which is sold separately)
2.
Connect the yellow (middle or common ) hose from
the manifold gauge to the vacuum pump.
MC
MC
Fig. 6.1
Air and foreign matter in the refrigerant circuit
BLUE (Low Pressure) Side of Manifold Gauge
RED (High Pressure) Side of Manifold Gauge
YELLOW (Common) Side of Manifold Gauge
BLUE (Low Pressure) Gauge
RED (High Pressure) Gauge
Low Pressure Valve
High Pressure Valve
LARGE DIA (GAS)
Service Valve
SMALL DIA (LIQUID)
Service Valve
Caution: Systems are precharged with refrigerant (entire amount necessary for the system set has been
charged into the outdoor section). The line sets and the indoor units are not charged, and must be evacuated
prior to releasing the refrigerant from the outdoor unit to the rest of the system.
Do NOT open the valves of the 2 service ports on your outdoor unit until the air evacuation is completed
successfully, and thw system passes leak checks. BOTH of those Service valves MUST BE OPENED to release the
refrigerant before turning the system ON. Operating the system with service valves closed will result in
compressor damage.
