In Canada refer to the current editions of the Canadian electrical Code CSA C22.1.
Recognize safety information. This is the safety-alert symbol 
. When you see this symbol on the unit and in instructions or manu- als, be alert to the potential for personal injury. Understand these signal words: DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies hazards which could result in per- sonal injury or death. CAUTION is used to identify unsafe practic- es which may result in minor personal injury or product and prop- erty damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.
!WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Before installing or servicing system, always turn off main power to system and install lockout tag. There may be more than one disconnect switch. Turn off accessory heater power switch if applicable.
!WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury, death or property damage.
A qualified installer or agency must use only factory-authorized kits or accessories when modifying this product.
!CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
When removing access panels (see Fig. 20) or performing maintenance functions inside your unit, be aware of sharp sheet metal parts and screws. Although special care is taken to reduce sharp edges to a minimum, be extremely careful when handling parts or reaching into the unit.
INTRODUCTION
The 604D--A heat pump is fully self-contained and designed for outdoor installation. (See Fig. 1.) Standard units are shipped in a horizontal-discharge configuration for installation on a groundlevel slab. Standard units can be converted to downflow (vertical) discharge configurations for rooftop applications.
RECEIVING AND INSTALLATION
Step 1 — Check Equipment
Identify Unit
The unit model number and serial number are stamped on the unit identification plate. Check this information against shipping papers.
Inspect Shipment
Inspect for shipping damage before removing packaging materials. If unit appears to be damaged or is torn loose from its anchorage, have it examined by transportation inspectors before removal. Forward claim papers directly to transportation company. Manufacturer is not responsible for any damage incurred in transit. Check all items against shipping list. Immediately notify the
nearest equipment distributor if any item is missing. To prevent loss or damage, leave all parts in original packages until installation.
If the unit is to be mounted on a curb in a downflow application, review Step 5 to determine which method is to be used to remove the downflow panels before rigging and lifting into place. The panel removal process may require the unit to be on the ground.
IMPORTANT: The unit must be secured to the curb by installing screws through the bottom of the curb flange and into the unit base rails. When installing large base units onto the common curb, the screws must be installed before allowing the full weight of the unit to rest on the curb. A minimum of six screws are required for large base units. Failure to secure unit properly could result in an unstable unit. See Warning near Rigging/Lifting information and accessory curb instructions for more details.
Step 2 — Provide Unit Support
Roof Curb
Install accessory roof curb in accordance with instructions shipped with curb (See Fig. 4). Install insulation, cant strips, roofing, and flashing. Ductwork must be attached to curb.
IMPORTANT: The gasketing of the unit to the roof curb is critical for a watertight seal. Install gasketing material supplied with the roof curb. Improperly applied gasketing also can result in air leaks and poor unit performance.
Curb should be level to within 1/4 in. (6 mm) (See Fig. 6). This is necessary for unit drain to function properly. Refer to accessory roof curb installation instructions for additional information as required.
Installation on older “G” series roof curbs.
Two accessory kits are available to aid in installing a new “G” series unit on an old “G” roof curb.
1.Accessory kit number CPADCURB001A00, (small chassis) and accessory kit number CPADCURB002A00, (large chassis) includes roof curb adapter and gaskets for the perimeter seal and duct openings. No additional modifications to the curb are required when using this kit.
2.An alternative to the adapter curb is to modify the existing curb by removing the outer horizontal flange and use accessory kit number CPGSKTKIT001A00 which includes spacer blocks (for easy alignment to existing curb) and gaskets for the perimeter seal and duct openings. This kit is used when existing curb is modified by removing outer horizontal flange.
!CAUTION
UNIT/STRUCTURAL DAMAGE HAZARD
Failure to follow this caution may result in property damage.
Ensure there is sufficient clearance for saw blade when cutting the outer horizontal flange of the roof curb so there is no damage to the roof or flashing.
Slab Mount
Place the unit on a solid, level concrete pad that is a minimum of 4 in. (102 mm) thick with 2 in. (51 mm) above grade (See Fig. 8). The slab should extend approximately 2 in. (51 mm) beyond the casing on all 4 sides of the unit. Do not secure the unit to the slab except when required by local codes.
Step 3 — Provide Clearances
The required minimum service clearances are shown in Fig. 2 and
3.Adequate ventilation and outdoor air must be provided. The outdoor fan draws air through the outdoor coil and discharges it through the top fan grille. Be sure that the fan discharge does not recirculate to the outdoor coil. Do not locate the unit in either a corner or under an overhead obstruction. The minimum clearance
