Tools Needed; First Stage Evacuation - Data Aire DAPA-2.5 Installation, Operation & Maintenance Manual

system must be purged with nitrogen. We recommend using a solenoid magnet tool to hold the liquid
line solenoid valve(s) open during this procedure.
A deep vacuum gauge capable of registering pressure in microns must be attached to the system on
the liquid line service port before TXV and should be at the farthest point in the system for most accurate
vacuum readings. A shutoff valve (suggest a Schrader valve core removal tool) between the system
and vacuum pump should be provided to allow the system pressure to be checked after evacuation.

Tools Needed

• Refrigerant manifold gauge set
• Vacuum rated hoses
• Nitrogen bottle
• Micron gauge
• Schrader valve core removal tool
• Two-Stage Vacuum Pump(s)
The vacuum pump should be connected to the discharge line after the check valve and the liquid line
before the metering device via vacuum rated hoses and Schrader valve core removal tools. On the high
side of the system there is a Schrader port located on the leaving side of the check valve and on the
liquid line before the expansion valve, attach your Schrader valve core removal tools and hoses here.
A micron gauge should be fitted to the system at the furthest point from the vacuum pump. Install a
Schrader valve core removal tool with shutoff valve before the micron gauge to prevent damage to the
micron gauge during charging.

First Stage Evacuation

1. With the refrigerant valves fully open, open the Schrader core shutoff valve and evacuate
the refrigerant lines, condenser coil and evaporator coil (the complete refrigerant system)
from both, low and high sides of the system to 2000 microns or less.
NOTICE: Do not turn OFF vacuum pump when connected to an evacuated
system before closing shutoff valve.
WARNING: Do not apply power to the compressor when in a vacuum.
NOTICE: This manifold gauge set should not be used for the vacuum
procedure.
NOTICE: Two pumps will speed up the procedure. One (1) vacuum pump
located normally outside at the condenser and one (1) vacuum pump is
located indoors at the evaporator unit.
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