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7. REFRIGERANT CONNECTIONS
Keep the coil connections sealed until refrigerant connections are
made. See the Installation Instructions for the outdoor unit for details
on line sizing, tubing installation, and charging information.
Coil is shipped with Nitrogen. Evacuate the system before charging
with refrigerant.
Install refrigerant tubing so that it does not block service access to
the front of the unit.
Nitrogen should flow through the refrigerant lines while brazing.
Use a brazing shield to protect the cabinet’s paint and a wet rag to
protect the rubber grommet and input pipe’s pistion seal ring from
being damaged by torch flames.
After the refrigerant connections are made, seal the gap around the
connections with pressure sensitive gasket.
Do not, under any circumstances, connect return ductwork to any
other heat producing device such as fireplace insert, stove, etc.
Unauthorized use of such devices may result in fire, carbon
monoxide poisoning, explosion, personal injury or property
damage.
Sheet metal ductwork run in unconditioned spaces must be insulated
and covered with a vapor barrier. Fibrous ductwork may be used if
constructed and installed in accordance with SMACNA Construction
Standard on Fibrous Glass Ducts. Ductwork must comply with
National Fire Protection Association as tested by UL Standard 181 for
Class I Air Ducts. Check local codes for requirements on ductwork
and insulation.
Duct system must be designed within the range of external static
pressure the unit is designed to operate against. It is important
that the system airflow be adequate. Make sure supply and return
ductwork, grills, special filters, accessories, etc. are accounted for
in total resistance. See airflow performance tables in this manual.
Design the duct system in accordance with “ACCA” Manual “D”
Design for Residential Winter and Summer Air Conditioning and
Equipment Selection. Latest editions are available from: “ACCA”
Air Conditioning Contractors of America, 1513 16th Street, N.W.,
Washington, D.C. 20036. If duct system incorporates flexible air
duct, be sure pressure drop Information (straight length plus all
turns) shown in “ACCA” Manual “D” is accounted for in system.
Supply plenum is attached to the 3/4” duct flanges supplied with
the unit. Attach flanges around the blower outlet.
IMPORTANT:
If an elbow is included in the plenum close to the
unit, it can not be smaller than the dimensions of the supply duct
flange on the unit.
IMPORTANT:
The front flange on the return duct if connected to
the blower casing must not be screwed into the area where the
power wiring is located. Drills or sharp screw points can damage
insulation on wires located inside unit.
Secure the supply and return ductwork to the unit flanges, using
proper fasteners for the type of duct used and tape the
duct-to-unit joint as required to prevent air leaks.
WARNING
6. DUCTWORK
Field ductwork must comply with the National Fire Protection
Association NFPA 90A, NFPA 90B and any applicable local
ordinance.
WARNING
Use a wet rag to protect the two seal ring in the input pipe from
being damaged by torch flames while brazing.
After the work is finished,make sure to check that there is no vapor
leak After checking for vapor leaks,be sure to insulate the piping
connections referring to Fig.10.
Fig.10 PIPING CONNECTIONS
Do not leave a gap
Vapor piping
Piping heat insulation
material
Liquid piping
Air
handler
Do not leave a gap
