Make sure that the fresh air vent is completely closed and that the discharge
grille and return air intake grille louvers are fully open.
Position an accurate thermometer directly in front of the return air intake grille
to measure dry bulb return air temperature.
Position another thermometer in front of the condenser air inlet guard to record
outside ambient air temperature. Make sure the thermometer is shaded fkom direct sunlight.
If indoor ambient temperature is too low, provide a space heater ta raise the dry
bulb return air temperature to 80(27C).
Turn the mode selector switch to COOL and the temperature selector switch to
Slowly open the unit service valves.
Allow the air conditioner to operate for at least 15 minutes in the COOL mode so
that all parts in the system are stabilized.
Record both inside and outside temperatures.
Record pressure readings.
Compare the pressure readings with the normal ranges shown in Table 5-3.
NORMAL TEMPERATURE-PRESSURE RELATIONSHIPS
95 F (35 C) dry bulb return air to unit