Make-Up Air Installation Manual

11/23/2011 2 EI904
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.
Visit our web site at electromn.com for upcoming service schools.
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
Insert this unit in a round duct arrangement. The air filtering and air moving devices are external to this unit.
FIGURE 1 shows a typical arrangement.
Note: A minimum of a 24” duct section is required at the outlet for installation of the temperature
sensing probe.
Clearance – Duct Surface Areas, Duct Installation, Etc.
When installed in an “inline” duct or round pipe adapter for a general distribution boost heater or air make-
up application, observe the following guidelines:
1. This product must be installed in a metal duct, size of the element rack.
2. There shall be no insulation on the inside of this sheet metal duct section.
3. Any flex-pipe or other insulated pipe must be at least 24” from the electric element.
4. Mounting – there must be at least 2” air clearance around all sides of the cabinet and sheet metal duct
section.
5. The control box must be positioned so it will not receive water dripping or collection of moisture.
6. See next section on duct sensor installation.
Duct Sensor
This unit is equipped with a remote temperature-sensing probe. This is a solid state probe (actually mini-micro
computer chip at the end of the probe), handle with care.
Suggested installation is in the main warm air stream approximately 20 to 24 airflow inches away from the
electric element. Simply drill a ½” hole in the duct, insert probe, and screw in place.
Comment: The sensor tip within the tube should be at the end of the tube or slightly extending beyond
the tube. If this is not the case, very carefully push the cable (do not grab the sensor tip with pliers) until
the sensor tip can effectively sample the warm air.
Coil and tie excess cable. It should be connected to the Red, ST, and COM screw terminals.
WARNING - If the black and red sensor wires are crossed or incorrectly installed at the terminal
block and power is turned on, burnout damage can result within the sensor probe.