System information

6
Provide clearances
The required minimum service clearances are shown in Figs. 1
and 2. 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 clear-
ance under a partial overhang (such as a normal house overhang)
is 1220 mm above the unit top. The maximum horizontal exten-
sion of a partial overhang must not exceed 1220 mm.
IMPORTANT: Do not restrict outdoor air flow. An air
restriction at either the outdoor air inlet or the fan discharge
may be detrimental to compressor life. Do not place the unit
where water, ice, or snow from an overhang or roof will
damage or flood the unit. Do not install the unit on carpeting
or other combustible materials. Slab-mounted units should be
at least 100 mm above the highest expected water and runoff
levels. Do not use unit if it has been under water.
Rig and place unit
Rigging and handling of this equipment can be hazardous for
many reasons due to the installation location (roofs, elevated
structures, etc.)
Only trained, qualified crane operators and ground support staff
should handle and install this equipment.
When working with this equipment, observe precautions in the
literature, on tags, stickers, and labels attached to the equipment,
and any other safety precautions that might apply. Follow all
applicable safety codes. Wear safety shoes and work gloves.
INSPECTION
Prior to initial use, and at monthly intervals, all rigging brackets
and straps should be visually inspected for any damage, evidence
of wear, structural deformation, or cracks. Particular attention
should be paid to excessive wear at hoist hooking points and
load support areas. Brackets or straps showing any kind of
wear in these areas must not be used and should be discarded.
INSTALLATION
1. Remove unit from shipping carton. Leave top shipping
skid on the unit as a spreader bar to prevent the rigging
straps from damaging the unit. If the wood skid is not
available, use a spreader bar of sufficient length to protect
unit from damage.
2. Position the lifting bracket assembly around the base of
the unit. Be sure the strap does not twist.
3. Place each of the 4 metal lifting brackets into the rigging
holds in the composite unit base.
4. Thread lifting bracket strapping around bottom perimeter
of unit as follows:
a. Open lever of tension buckle (ratchet type).
b. Feed strapping through tension buckle as shown in
Fig. 7.
c. Pull strapping through tension buckle unit taut.
d. Snap lever down to lock strap in tension buckle. To
release strapping, squeeze safety latch, lift lever, and
pull webbing outward.
5. Tighten the tension buckle until it is taut. Lifting brackets
must be secure in the rigging holds.
6. Attach field-supplied clevis or hook of sufficient strength
to hole in the lifting bracket (Fig. 8)
7. Attach the two safety straps directly to the clevis or hook
at the four rigging brackets. DO NOT attach the safety
straps to the lifting brackets (Fig. 8)
8. Position lifting point directly over the unit centre of
gravity.
9. Lift unit. When unit is directly over the roof curb, remove
the two safety straps. Lower the equipment onto the roof
curb.
10. After the unit is placed on the roof curb or mounting pad,
remove the top crating.
Select and install duct work
The design and installation of the duct system must be in
accordance with applicable standards for installation of non-
residence type air conditioning and ventilating systems.
Select and size duct work, supply air registers, and return air
grilles according to standard HVAC recommendations.
The unit has duct flanges on the supply- and return-air
openings on the side of the unit. When designing and installing
duct work, consider the following:
WARNING: For vertical supply and return units, tools or
parts could drop into duct work and cause serious injury or
death. Install a 90 degree turn in the return duct work
between the unit and the conditioned space. If a 90 degree
elbow cannot be installed, then a grille of sufficient strength
and density should be installed to prevent objects from falling
into the conditioned space. Units with electric heaters require
90 degree elbow in supply duct.
1. All units should have field-supplied filters or accessory
filter rack installed in the return-air side of the unit.
Recommended sizes for filters are shown in Table 1.
2. Avoid abrupt duct size increases and reductions. Abrupt
change in duct size adversely affects air performance.
IMPORTANT: Use flexible connectors between duct work
and unit to prevent transmission of vibration. Use suitable
gaskets to ensure weather tight and airtight seal. When
electric heat is installed, use fireproof canvas (or similar heat
resistant material) connector between duct work and unit
discharge connection. If flexible duct is used, insert a sheet
metal sleeve inside duct. Heat resistant duct connector (or
sheet metal sleeve) must extend 610 mm from electric heater
element.
3. Size duct work for cooling air flow. The minimum air
flow for proper electric heater operation is listed in Table
2. Heater limit switches may trip at air quantities below
those recommended.
4. Seal, insulate, and weatherproof all external duct work.
Seal, insulate and cover with a vapour barrier all duct
work passing through conditioned spaces.
5. Secure all ducts to building structure. Flash, weatherproof,
and vibration-isolate duct openings in wall or roof
according to good construction practices.