INSTALLING THE CONDENSING UNIT (continued)
Page 32
Liquid Line King Valve
This location is used to charge the system with liquid refrigerant
and identify the high side pressure of the system.
Calculating Subcooling
To determine the subcooling of the system, calculate the difference between the
high side pressure of the system
(converted to temperature)
and the
temperature of the liquid line
. The temperature of the liquid line will be taken on
the exterior of the condensing unit, about 4" away from the housing.
*Saturation temp — liquid line temp
5
-15
°F
SUBCOOLING REQUIRED FOR WARRANTY APPROVAL
Pressure Test
After the line set has been connected securely to the evaporator and condensing unit, remove valve stem caps from low pressure
(suction) and high pressure (liquid) valves on condensing unit.
If desired, r
emove (schrader) valve cores from valves using valve core
removal tool.
Ensure service valve stems are in the back-seated position.
If valve cores have been removed, they
should be reinstalled
in valves after pressure testing, vacuum, and charging procedures are complete
.
Connect charge hoses of the manifold gauge to the service ports on the outdoor unit’s low pressure and high pressure valves. Leave
gauge manifold knobs in closed position until nitrogen is ready to be admitted into the system. Connect service hose from service
port on manifold to nitrogen regulator. Set nitrogen tank regulator to approximately
2
25
psi. Open both high side and low side gauge
manifold knobs SLOWLY at the same time to admit nitrogen into the system until the gauge manifold reads
225
psi, then close gauge
manifold knobs. Let pressure stand for minimum of 10 minutes. Use soapy solution to check flare connection points for leaks. If no
leaks are present and pressure is maintained after 10 minutes of pressure test
,
p
roceed with evacuation process. If any leak is
detected, it must be corrected before moving onto evac
u
ati
o
n process.
•
Remove the nitrogen from the system
•
Remove the nitrogen tank from the manifold and attach the manifold to the vacuum pump
•
Install service caps on the valves.
•
After confirming that there is fresh oil in the vacuum pump, connect the hose from the manifold to the
pump.
•
Start the pump and run it until micron gauge reads
2
50 microns or less.
•
Once vacuum of
2
50 microns or less is achieved, d
isconnect the vacuum pump from the system.
•
Remove the micron gauge from the access valve.
•
Close the valves on the manifold
Air Evacuation/ Vacuum
Note: For adjusting the service valves on the condensing unit a
3
/
16
" allen wrench is needed.
Wall
Mount H.E.
Line Set Length
<25ft
26-50ft
50-100ft
Suction Line
Horizontal Tubing
3
/
8
”
Vertical Rise
Liquid Line
Horizontal Tubing
1/4”
Vertical Rise
1/4”
1/2”
3
/
8
”
Line Set Piping Size
Line set piping size is determined by the unit size and the line set length. Determine the length before selecting the size.
For the vertical rise on the suction and liquid lines refer to the line set piping
examples previously shown
. When the
condensing unit is mounted about the evaporator unit
it is recommeded that
the
suction
line
should
have
oil saving bends
placed every 1
5'.
