Make-Up Air Installation Manual

01/17/2013 EI902
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Description
This is more than a traditional duct heater. The control box and electric elements may appear to be a
standard duct heater, but the internal WarmFlo controller and its companion solid state temperature sensor
modulate the duct heater elements to produce a constant outlet temperature at the sensor.
This unit applies to forced air ducts (blower within system). Do not install in a fresh air duct which depends
upon gravity or building pressure differential flow. See Table 1 for min. CFM.
240-Volt Rating – Single Phase – Models
When operating at a lower source voltage the output may be reduced.
Example: 10 KW unit assuming normal element tolerances.
- 220-volt source – 16.8 KW, 76 amps
- 208-volt source – 15.1 KW, 72 amps
208-Volt Rating – Three Phase – Models
When all elements are on, it is a three phase balance load. Measure current in each leg and apply three phase
formula to determine kW.
Installation Requirements
1. All installation work must be performed by trained, qualified contractors or technicians. Electro
Industries, Inc., sponsors installation and service schools to assist the installer.
2. All electrical wiring must be in accordance with national electric codes and local electric codes,
ordinances, and regulations.
3. Observe electric polarity and wiring colors. Failure to observe could cause electric shock and/or
damage to the equipment.
4. This unit can only be used for its intended design as described in this manual. Any internal wiring
changes, modifications to the circuit board, modifications or bypass of any controls, or installation
practices not according to the details of this manual will void the product warranty, the ARL
certification label, and manufacturer product liability. Electro Industries, Inc., cannot be held
responsible for field modifications, incorrect installation, and conditions which may bypass or
compromise the built-in safety features and controls.
Mechanical Installation
Warning - In order to provide maximum electric element life, the airflow through all electric
elements must be uniform.
Typical installation is within a horizontal forced air duct. The element rack for these models is 8x16” deep.
Observe airflow arrow decal and orientate the unit so the airflow is through the elements as represented by
the airflow decal arrow.
Using correct placement and deflectors, make every effort to make sure at least 90% of the air passes through
the element rack.
If installation is within 4 feet of any elbow, plenum or tee; turning veins will be required to make sure there
is uniform airflow through the element rack.
Secure control box to duct.