Instructions / Assembly

The air distribution system has the greatest effect on airflow. The duct system is totally controlled by
the contractor. For this reason, the contractor should use only industry-recognized procedures.
Heat pump systems require a specified airflow. Each ton of cooling requires between 350 and 450
cubic feet of air per minute (CFM), or 400 CFM nominally. Duct design and construction should be
carefully done. System performance can be lowered dramatically through bad planning or
workmanship.
Air supply diffusers must be selected and located carefully. They must be sized and positioned to
deliver treated air along the perimeter of the space. If they are too small for their intended airflow,
they become noisy. If they are not located properly, they can create drafts. Return air grilles must be
properly sized to carry air back to the blower. If they are too small, they also cause noise.
The installers should balance the air distribution system to ensure proper, quiet airflow to all rooms in
the home. This ensures a comfortable living space. An air velocity meter or airflow hood can give a
reading of system CFM.
INDOOR UNIT
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11 ELECTRICAL DATA
Table 3
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 “No charge”. 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 from
being damaged by torch flames. After the refrigerant connections are made, seal the gap around the
connections with a pressure sensitive gasket.
12 REFRIGERANT CONNECTIONS