CCI Thermal Technologies DIT - Insert Air Duct Heater (Non-Finned Tubular Elements - Calrod type*) - Manuel

CCI Thermal Technologies Inc. 2767 Brighton Road, Oakville, ON L6H 6J4 Tel. (905) 829-4422 Fax (905) 829-4430
www.ccithermal.com
MI123 REV.5 Page 1 of 2
1.0 PRE-INSTALLATION
1.1 Inspect the heater for possible damage due to shipping
and handling. Claims for shipping damages shall be placed with
the carrier.
1.2
Check the heater nameplate to ensure that the voltage
and phase are the same as the supply voltage and phase.
2.0 DESCRIPTION
2.1 GENERAL
Caloritech™ air duct heaters are designed for use in comfort
heating applications. Two basic heater frame constructions are
available; flange type or insert type (see Figures 1 & 2 below).
INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
FOR COMMERCIAL DUCT HEATERS
Figure 1 - Flange Type Figure 2 - Insert Type
Type DFF is a flanged duct heater with finned tubular heating
elements.
Type DIF is an insert duct heater with finned tubular heating
elements.
Type DFT is a flanged duct heater with incoloy (non-finned)
tubular heating elements.
Type DIT is an insert duct heater with tubular heating elements.
2.2 ELEMENT TYPES
The finned tubular element design incorporates the highest
wattage per cross sectional duct area.
Finned tubular elements are constructed using a steel element
with a steel fin coiled around it and then brazed together. This
increases the heat transfer surface of the element.
Figure 3 - Finned Tubular Element
Incoloy tubular elements are similarly constructed, but without
the steel fin in order to increase the corrosion resistance. They
usually operate at higher temperatures than finned elements.
The incoloy design is chosen when high humidity or slightly
corrosive chemical contaminants are present in the air stream.
These units are made and approved on special order only.
Figure 4 - Tubular Element
Both element types are designed to provide many years of
maintenance free service.
Unlike open coil designs, duct heaters fitted with tubular elements
are not subject to hazards of electrical shock which allows
installation close to a register or grille.
2.3 HIGH LIMIT PROTECTION
Each Caloritech™ electric duct heater is equipped with one or
two high limits (based on the installed capacity and voltage) which
will shut off the heater in the event of an overtemperature situation.
CSA requires that duct heaters rated 30kW and less, with a voltage
rating of 300V and less, be equipped with a secondary
temperature limiting control that has a manual reset and a separate
means of power disconnection (i.e. backup contactor).
The installed high limit(s) are factory preset at temperatures to
protect your system. The set points are:
Automatic reset 71°C(160°F)
Manual reset 107°C(225°F)
3.0 INSTALLATION
3.1 Finned tubular duct heaters are approved for horizontal
duct installation where the maximum inlet air temperature does
not exceed 25°C(77°F) and the maximum rating does not exceed
120kW. Multiple heaters can be installed in tandem (series)
provided that the inlet temperature to any heater section (one
heater) is not more than 25C(77°F) and the air velocity is not less
than the requirements of Figure 5 (see over).