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Insulate the 3/8” suction line with the 10” piece of supplied cork tape.
Refrigerant Piping Procedures
When installing/routing the lines set, cap both ends of each tube to prevent material or debris from entering the
tubing.
Prior to connecting the piping, loosely connect the refrigerant gauges to the service ports of the suction and liquid
line service valves. Purge the charging hoses with dry Nitrogen and tighten the hose connections. Remove the service
valve caps and turn the valve stem clockwise (half of a complete turn) in order to unseat the valve and open the
service port. The valve comes in a back seated position from the factory. Keep the piping port sealed until ready to
connect to the vacuum pump.
Cleanliness is of the utmost importance. All horizontal suction piping should be pitched toward the condensing unit
Insulation Adhesive or equivalent. Wrap each seam using line set tape.
Liquid Line Piping Procedure
It is required to use a 1/4” OD Copper tube liquid line. When making connections keep the ends sealed until ready to
Downstream, connect the moisture indicating sight glass in an easily visible location. Run the tubing to the Evaporator
Evaporator Unit (Fan Coil Unit) and set the temperature controller to call for cooling, this will activate the liquid line
Suction Piping Procedure
Unit (Fan Coil Unit) outlet connection. Install a Schrader Type Access valve at the outlet of the Evaporator Unit (Fan
after leak testing.
After all piping ran and ready for the brazing process: Energize the Evaporator Unit (Fan Coil Unit) and set the
temperature controller to call for cooling. Open the liquid line service valve and bleed the nitrogen through both
the liquid and suction line. Loosen the suction gauge hose to relieve pressure during the brazing process. Braze the
add a small amount of 134a to both the high and low sides.
Leak Testing
Using Dry Nitrogen pressurize the system to 200 PSI. Check to see if there is a noticeable pressure drop, if so locate and
there are no leaks, release the nitrogen pressure and leave the solenoid valve energized.
INSTALLING THE CONDENSING UNIT