Installation Manual
Page 28mrcool.com
Refrigerant Piping Connection
BEFORE PERFORMING EVACUATION
Check to make sure that both 
high-pressure and low-pressure 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.
Preparations and Precautions
Evacuation Instructions
Before using the manifold gauge and vacuum pump, 
read their operation manuals to familiarize yourself 
with how to use them properly.
MC MC
Manifold Gauge
Compound gauge
-76cmHg
Low pressure valve
High pressure 
valve
Pressure hose
/ Charge hose
Charge hose
Vacuum
pump
Pressure gauge
Low pressure valve
Fig. 7.1
Air and foreign matter in the refrigerant circuit 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 refrigerant circuit, removing 
any non-condensable gas and moisture from the 
system. Evacuation should be performed upon initial 
installation and when unit is relocated.
1.  Connect the charge hose of the manifold gauge to
 service port on the outdoor unit’s low-pressure
 valve.
2. Connect another charge hose from the manifold
 gauge to the vacuum pump.
7
Air Evacuation










