Payne PA3A Installation Instructions Manual page 4

CAUTION
!
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper
product operation.
Do not bury more than 36" (914 mm) of line set
underground. Refrigerant may migrate to cooler buried
section during extended periods of unit shut- -down, causing
refrigerant slugging and possible compressor damage at
start- -up.If ANY section of the line set is buried
underground, provide a minimum 6" (152 mm) vertical rise
at the service valve.
D. OUTDOOR UNIT HIGHER THAN INDOOR UNIT
Proper oil return to the compressor should be maintained with
suction gas velocity. If velocities drop below 1500 fpm (feet per
minute), oil return will be decreased. To maintain suction gas
velocity, do not upsize vertical suction risers. Use the "<80 feet (24
m)" suction line sizes shown Table 1.
Install oil traps every 20 feet (6 m) of vertical suction line riser.
E. LIQUID LINE FILTER- -DRIER
Outdoor units are shipped with an appropriate filter- -drier for
installation in the liquid line. Leave the plugs in the tube ends until
the filter- -drier is installed. The optimal location for the filter- -drier
is close to the indoor coil. Install the filter- -drier with the arrow
pointing towards the indoor coil. Refer to Fig. 4.
Fig. 4 --- Liquid Line Filter Drier Installed at Outdoor Unit
F. SERVICE VALVES
Service valves are closed and tube stubs are plugged from the
factory. Outdoor units are shipped with a refrigerant charge sealed
in the unit. Leave the service valves closed until all other
refrigerant system work is complete or the charge will be lost.
Leave the plugs in place until line set tubing is ready to be inserted.
Service valve bodies are brass and tube stubs are copper.
G. BRAZING CONNECTIONS
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Refrigerant and oil mixture could ignite and burn as it
escapes and contacts brazing torch. Make sure the refrigerant
charge is properly removed from both the high and low sides
of the system before brazing any component or lines.
Clean line set tube ends with emery cloth or steel brush. Remove
any grit or debris.
Insert line set tube ends into service valve tube stubs.
Apply heat absorbing paste or heat sink product between service
valve and joint. Wrap service valves with a heat sinking material
such as a wet cloth.
Braze joints using a Sil- -Fos or Phos- -copper alloy.
PRODUCT DAMAGE HAZARD
Failure to follow this caution may result in product damage.
Braze
copper- -to- -copper joints and wrap a wet cloth around rear
of fitting to prevent damage to TXV.
H. EVACUATING LINE SET AND INDOOR COIL
The unit is shipped with a factory refrigerant charge. The liquid
line and suction line service valves have been closed after final
testing at the factory. Do not disturb these valves until the line set
and indoor coil have been evacuated and leak checked, or the
charge in the unit may be lost.
NOTE: Do not use any portion of the factory charge for purging
or leak testing. The factory charge is for filling the system only
after a complete evacuation and leak check has been performed.
PRODUCT DAMAGE HAZARD
Failure to follow this caution may result in product damage.
Never use the outdoor unit compressor as a vacuum pump.
Doing so may damage the compressor.
Line set and indoor coil should be evacuated using the
recommended deep vacuum method of 500 microns. If deep
vacuum equipment is not available, the alternate triple evacuation
method may be used by following the specified procedure.
If vacuum must be interrupted during the evacuation procedure,
always break vacuum with dry nitrogen.
Deep Vacuum Method
The deep vacuum method requires a vacuum pump capable of
pulling a vacuum to 500 microns and a vacuum gauge capable of
accurately measuring this vacuum level. The deep vacuum method
is the most positive way of assuring a system is free of air and
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water.
Watch the vacuum gauge as the system is pulling down. The
response of the gauge is an indicator of the condition of the system.
With no leaks in the system, allow the vacuum pump to run for 30
minutes minimum at the deep vacuum level.
Triple Evacuation Method
The triple evacuation method should only be used when system
does not contain any water in liquid form and vacuum pump is
only capable of pulling down to 28 inches (711 mm) of mercury.
Proceed as follows:
3. Pull system down to 28 inches (711 mm) of mercury and
4. Close manifold valves or valve at vacuum pump and shut
5. Connect a nitrogen cylinder and regulator to system and fill
6. Close nitrogen valve and allow system to stand for 1 hour.
7. Repeat this procedure.
8. After the final evacuate sequence, confirm there are no leaks
4
CAUTION
!
with Sil- -Fos or Phos- -copper
CAUTION
!
allow pump to continue operating for an additional 15
minutes.
off vacuum pump.
with nitrogen until system pressure is 2 psig.
During this time, dry nitrogen will diffuse throughout the
system absorbing moisture.
in the system. If a leak is found, repeat the entire process
after repair is made.
alloy on