16
Floor and Ceiling Unit
Refrigerant Piping Requirements
Note: Until the outdoor unit is set and ready to connect refrigeration pipes, do not remove the
caps from the indoor unit.
NOTICE
1. Connect each pipe to its port on the indoor unit correctly. If the centering is improper, the
flare nut cannot be tightened smoothly. If the flare nut is forced to turn, the threads will be
damaged. Refer to the flaring process guidelines in this manual for additional information.
2. Do not remove the tube caps nut until the connection pipe is made ready to prevent dust and
impurities from entering the system.
1. When connecting refrigerant pipe to the unit or removing it from the unit, please use both a
back-up wrench and the torque wrench. See illustration on page 17.
2. When connecting, place the equipment specified oil type on the backside of the copper
tube flare prior to tightening. Do not place oil on the flare face, as this will promote system
contamination, tighten it by hand and then tighten it with the spanner or adjustable wrench.
3. Refer to the torque reference table within this document before tightening to determine the
appropriate torque (over-tightening will damage the nut and lead to leakage).
4. Use dry Nitrogen to pressurize the piping circuit with 150 PSIG and allow it to hold while
performing other installation processes. It is recommended to apply a soap bubble solution and
observe the connection.
5. Evacuate each individual refrigeration circuit to 350 microns or below, and close off the valve to
the vacuum pump. If the pressure rises above 500 microns within one minute, but not above
1500 microns within 5 minutes, moisture is present. If the pressure continues to rise above
1500 microns, a leak exists in the circuit being tested.
a) If moisture is present, use triple evacuation process to eliminate the moisture.
b) If a leak is present, leak check all joints and piping.
Evacuation is not completed until the micron gauge does not rise above 500 microns within
one minute after achieving 350 micron pressure vacuum.
6. After evacuation is complete, additional charge can be added.
a) If no additional charge is required, break the vacuum with refrigerant, then remove the
gauge connectors.
b) slightly open the liquid valve at the OD unit, allow system to equalize, then fully open
the liquid valve and then open the vapor service valve.
7. After leak checking is complete, apply thermal insulation around the flare connections and
all exposed refrigeration pipes Refer to the guidelines for insulating refrigerant piping and
connections in this manual for additional information.
a) Seal the insulation
b) Inspect the insulation to assure no breakages are present.
NOTE: Use Dry Nitrogen for leak checking purposes. Never use oxygen, compressed air, or any
flammable gas for leak checking purposes.
