Installation - Chromalox ADH-005 Installation Instructions Manual

Installation

ELECTRIC SHOCK HAZARD. Disconnect all power
before installing or servicing heater. Failure to do
so could result in personal injury or property dam-
age. Heater must be installed by a qualified person
in accordance with the National Electrical Code,
NFPA 70. The system designer is responsible for the
safety of this equipment and should install adequate
back-up controls and safety devices with their elec-
tric heating equipment. Where the consequences
of failure could result in personal injury or property
damage, back-up controls are essential.
1. Locate and position heater in duct in accordance with
both process requirements and recommendations given.
2. Refer to Figures 1 and 2, layout "D" and "M" dimensions
on duct mounting face established in step 1.
3. With tools suitable for sheet metal work, cut layout open-
ing in duct.
4. In general, heaters less than 35 pounds in weight may
be mounted directly in opening without additional duct
reinforcement if duct installation and condition permits.
To fasten heater to duct wall use #14 pan or round head
self-tapping screws. The flange mounting gasket sup-
plied with the heater is recommended for insertion be-
tween heater flange and duct to minimize air leakage.
5. For heater weights greater than 35 pounds (see Speci-
fications Table A, page 1) due consideration should be
given to; (a) mechanically strengthening duct work with,
for example, angle irons or chains (see Figure 5), and (b)
heat insulating duct line in immediate area of heater loca-
tion to prevent excessive heat loss. Consult your local
sheet metal contractor.
Duct
Heater
Opening
Angle Iron
Figure 5
6. In high ambient temperature operations, least corrosive
action and least oxidation to the terminals will occur if
the heaters are mounted with the terminals in the coolest
possible ambient, usually on the bottom or side of the
duct.
A. Minimum duct size is "A" or "L" dimension +3/8" and
"B" dimension +1-5/8".
ADH Low temperature duct heaters — can be fas-
tened directly to the sheet metal duct work with bolts or
sheet metal screws.
Duct
Air
Air
Figure 6
Chains
Duct
Metal
Strapping
Heater Opening
ADHT High temperature duct heaters — are generally
mounted on field fabricated stand off supports from the
ductwork to position the heater such that the 3" insulation
housing is in the same plane as the duct insulation.
Duct
Air
Air
Figure 7
Temperature Control Instructions
1. A Chromalox thermal cutout or thermostat is recom-
mended for overheat protection and control of heater
and process. Consult local Chromalox representative.
2. In general, place thermostat sensing element close to the
heating elements, near top of duct, at right angles to the
direction of air flow, and on the downstream side of the
heater. Thermostat, provided with a manual reset button,
is separately mounted.
HAZARD OF FIRE. Since these heaters are capable
of developing high temperatures, extreme care
should be taken to:
A. Avoid installing heaters in an atmosphere containing
combustible gases and vapors.
B. Avoid contact between heater and combustible mate-
rial.
C. Keep combustible materials far enough away to be
free of the effects of high temperatures.
3. For heater protection, the indicated maximum tempera-
ture of the control unit should be 50°F less than the ac-
tual maximum air temperature that will be permitted, to
allow for overshoot.
4. Single circuit heater elements may be wired into two cir-
cuits to allow for partial heating and control. It is impor-
tant to have thermal control wired into all electric power
circuits, so that all elements may be protected from over-
heat.
5
Standoff Collar
Insulation
(3" max.)