unIT mounTIng
cAUTION
1. Do not install units below 7' measured from the bottom of
the unit to the floor in commercial applications (unless
unit is properly guarded to provide user protection from
moving parts) and 5' measured from the bottom of the unit
to the floor in residential applications.
2. Be sure no obstructions block air intake and discharge
of unit heaters.
3. The minimum distance from combustible material is
based on the combustible material surface not exceeding
160°F. Clearance from the top of the unit may be required
to be greater than the minimum specified if heat damage,
other than fire, may occur to materials above the unit
heater at the temperature described.
4. Allow 18" clearance at rear (or 6" beyond end of motor
at rear of unit, whichever is greater) and access side to
provide ample air for proper operation of fan.
1. Be sure the means of suspension is adequate to support
the weight of the unit (see page 16 for unit weights).
2. For proper operation, the unit must be installed in a level
horizontal position.
3. Clearances to combustibles as previously specified must be
strictly maintained.
4. For model sizes 30-75, before lifting the heater for
suspension, the mounting brackets must be installed as
follows (for bracket accessory installation on model sizes
100-125, see the latest revision of literature 6-594):
• For standard (left side) control access, remove the (3)
screws and mounting bracket along the top edge of both
the front and back of the unit. Install the front bracket as
shown in Figure 5.1 by aligning the screw holes on the
bracket with the screw holes on the top edge of the unit.
Repeat for the bracket on the back of the unit.
• For right side control access, remove the (3) screws and
mounting bracket along the top edge of both the front and
back of the unit. Turn the unit over and install the front
bracket as shown in Figure 5.2 by aligning the screw holes
on the bracket with the screw holes on the top edge of the
unit (originally the bottom edge). Repeat for the bracket on
the back of the unit.
5a. suspension by screws/lag bolts: Secure the mounting
brackets to the ceiling joists or truss, using 1/4" screws with
1/2" washers. These unit mounting brackets are slotted to
accommodate joists on 16" or 24" centerlines. See page 16
for mounting bracket dimensions.
figure 5.1 - unit Heater in standard mounting
Configuration (30-75 units only)
figure 5.2 - unit Heater Turned 180° (30-75 units only)
(Access panel and heated air outlet change sides)
5b. suspension by threaded rod: The unit can also be hung
with threaded rod utilizing the same mounting brackets.
Attach the threaded rod to the unit mounting brackets,
securing with a top and bottom nut. For model sizes
100-125, the units are designed to be suspended by
threaded rod without the use of brackets. On each piece of
3/8" threaded rod used, screw a nut a distance of about one
inch onto the end of the threaded rods that will be screwed
into the unit heater. Place a washer over the end of the
threaded rod and screw the threaded rod into the unit heater
weld nuts on the top of the heater at least 5 turns, and no
more than 10 turns. Tighten the nut first installed onto the
threaded rod to prevent the rod from turning.
Next, drill holes into a steel channel or angle iron at the
same centerline dimensions as those chosen for the heater
being installed. The steel channels or angle iron pieces need
to span and be fastened to appropriate structural members.
Cut the threaded rods to the preferred length, push them
through the holes in the steel channel or angle iron and
secure with washers and lock nuts, lock washers and nuts,
or a washer with double nut arrangement.
noTe: A pipe hanger adapter kit, shown in Figure 5.3, is
available as an accessory. One kit consists of two drilled
3/4" IPS pipe caps and two 3/8 - 13 x 1-3/4" capscrews
to facilitate threaded pipe suspension. Two kits would be
required.
5c. shelf mounted units: The unit heater can also be installed
on a shelf. The mounting brackets will need to be attached
to the heater the same manner as explained in note #4,
however, to mount on a shelf the brackets must go on the
bottom of the heater. The brackets must be affixed to the
shelf using similar screws (1/4" screw with 1/2" washer) as
overhead joist or truss mounting. Be sure all clearance to
combustible requirements are met.
figure 5.3 - unit Heater suspension methods
(Threaded Rod)
6-584.2
(Pipe Adaptor Kit)
5