Installation, Caution – Comfort-Aire WDG Air Handler Series User Manual
Page 11

11
Installation, Operation & Maintenance
WDG AIR HANDLER SERIES
Heat Controller, LLC
CAUTION!
CAUTION! Installation of a factory supplied liquid line bi-
directional fi lter drier is required. Never install a suction line
fi lter in the liquid line.
CAUTION!
See compressor section IOM for refrigerant charge
information.
Line Set Installation
Figure 4 illustrates a typical installations of an air handler l matched
to an indoor compressor section. Table 1 shows typical line-set
diameters at various lengths. Lineset lengths should be kept to a
minimum and should always be installed with care to avoid kinking.
Line sets over 60 feet [18 meters] long are not recommended due to
potential oil transport problems and excessive pressure drop. If the
line set is kinked or distorted, and it cannot be formed back into its
original shape, the damaged portion of the line should be replaced.
A restricted line set will effect the performance of the system.
All brazing should be performed using nitrogen circulating at
2-3 psi [13.8-20.7 kPa] to prevent oxidation inside the tubing.
All linesets should be insulated with a minimum of 1/2” [13mm]
thick closed cell insulation. All insulation tubing should be
sealed using a UV resistant paint or covering to prevent
deterioration from sunlight.
When passing refrigerant lines through a wall, seal opening
with silicon-based caulk. Avoid direct contact with water
pipes, duct work, fl oor joists, wall studs, fl oors or other
structural components that could transmit compressor
vibration. Do not suspend refrigerant tubing from joists
with rigid straps. Do not attach line set to the wall. When
necessary, use hanger straps with isolation sleeves to
minimize transmission of line set vibration to the structure.
Installing the Indoor Coil and Lineset
Figure 3 shows the installation of the lineset and TXV to a typical
indoor coil. Braze the copper line set to the coil. Nitrogen should be
circulated through the system at 2-3 psi
[13.8-20.7 kPa] to prevent
oxidation inside the refrigerant tubing. Use a low silver phos-copper
braze alloy on all brazed connections.
Installation
Figure 3: Air Coil Connection
TXV (‘IN’ toward
compressor section)
Suction Line
Liquid Line
Bulb
(Must be
Installed and
Insulated)
Equalizer
Line
TXV has internal
check valve
NOTICE! The air coil should be thoroughly washed with a fi lming
agent, (dishwasher detergent like Cascade) to help condensate
drainage. Apply a 20 to 1 solution of detergent and water. Spray
both sides of coil, repeat and rinse thoroughly with water. Care
should be taken not to overfl ow drain pan. Wash after connecting
condensate line.
Sensing Bulb
IMPORTANT: DO NOT perform any brazing with the TXV
bulb attached to any line. After brazing operations have been
completed, clamp the TXV bulb securely on the suction line at
the 10 or 2 o’clock position with the strap provided in the parts
bag. Insulate the TXV sensing bulb and suction line with the
provided pressure sensitive insulation (size 4” x 7”).
IMPORTANT: TXV sensing bulb should be located on a horizontal
section of suction line, just outside of coil box.
IMPORTANT: Always protect TXV from heat when brazing.
IMPORTANT: TXV sensing bulb is shipped unattached. Installer
must attach bulb to suction line after brazing and cooling line for
proper unit operation.
CAUTION! HFC-410A systems operate at higher pressures
than R-22 systems. Be certain that service equipment
(gauges, tools, etc.) is rated for HFC-410A. Some R-22 service
equipment may not be acceptable.
Figure 4: Typical Split/Air Handler Installation
Compressor Section
Low Voltage
Insulated
Linesets
Air pad or Extruded
polystryene
PVC Condensate
with vented trap
Power
Disconnects
Air
Handler
Low
Voltage
Return
Plenum