Sterling VS - Manual (Page 15)

15
INSTALLATION
It is assumed that the design engineer has selected,
sized, and located in the area to be heated by the design
engineer. However, the information given here may be of
additional help to the installer.
Vertical unit heaters should be located to give spot
heating or a circulatory distribution, preferably near the
outer perimeter of the building. The units should be
spaced to properly blanket the areas with warm air. Place
the units at points of greatest heat loss. Blanket outside
doorway and provide ample coverage of window areas.
Keep units away from obstructions that will impede the
full and natural air delivery of the units.
Install unit heaters to meet ETL and OSHA requirements;
Vertical Unit Heaters mounted lower than 2.4 meters (8
feet) from the fl oor must be equipped with an OSHA fan
guard. Weldnuts are provided at the top of all units for
suspension purposes. The unit should be suspended
from connections provided in the unit by means of rods.
The rods should then be attached to solid supports of
the building.
Units must hang level vertically and horizontally.
Provide sufficient clearance around units for
maintenance purposes. This includes at least 7 inches
above all Vertical Unit Heaters even though the motor is
removable through the bottom. To provide effi cient airfl ow
to the unit, maintain a clearance of 2 feet (0.61m) aound
all sides of the unit.
Isolators are not required but may be desirable for some
applications. Refer to Table 15 for Unit Weights.
Table 15 – Unit Weights-Lbs
VERTICAL UNIT HEATERS
Approx. Ship
Unit Weight (Lbs.)
40 32
62 40
77 43
104 63
125 64
144 80
164 80
200 86
237 134
285 139
317 139
367 146
495 294
585 307
700 366
Make certain that the lifting
methods used to lift the heater and the method
of suspension used in the fi eld installation of the
heater are capable of uniformly supporting the
weight of the heater at all times. Failure to heed
this warning may result in property damage or
personal injury!
Make certain that the structure
to which the heater is mounted is capable of
supporting its weight. Under no circumstances
must the piping or the electrical conduit be used
to support the heater; or should any other objects
(i.e. ladder, person) lean against the heater or the
electrical conduit for support.
Unit heaters must be hung level
from side to side and from front to back. Failure
to do so will result in poor performance and or
premature failure of the unit.
Ensure that all hardware used in
the suspension of each unit heater is more than
adequate for the job. Failure to do so may result
in extensive property damage, severe personal
injury or death.
EXAMPLE
Table 18 lists maximum mounting height and fl oor spread
data of warm air coverage at fl oor level with louver cone
diffusers. Correction factors for various water temp. and
PSI of steam are in Table 19.
An approximation of the fl oor spread when operating on
other than 2 lb. Steam or 219 degree may be obtained by
ratioing the new fl oor spread and the maximum mounting
height to that at 2 lb. steam or 219 degree hot water.
Following is an example:
Determine the fl oor spread and the maximum mounting
height of a std. model 77 unit heater with a cone diffuser
set at 90 degrees, operating on 280 degree hot water.
From Table 18, maximum mounting height of a model
77 at 219 degree hot water is 18.5 ft. with fl oor coverage
of 14.0 ft. diameter. The maximum mounting height
correction factor at 280 degree hot water is 0.80.
18.5 ft. x 0.80 = 14.8 ft.
Maximum mounting height of a model 77 using 280 degree
hot
water.
“X” = fl oor spread of model 77 using 280 degree hot water.
X = 14.8 x 14.0 / 18.5
X = 207.2 / 18.5
X = 11.2 ft.