
PHOTO-CATALYTIC AIR PURIFIER SYSTEMS
Models: DUO-11/24V, DUO-14/24V, PCUV-16UA
ITEMS INCLUDED IN KIT:
1-24Volt UV-Aire Ballast Assembly
1-Photo-Catalytic Duct Insert
1-UVC Germicidal Lamp
4-Sheet Metal Mounting Screws
1-Instruction Sheet
1-Duct Board Mounting Bracket
1-24V Transformer
2-Fork Terminals
2-Wire Nuts
The Duo 24V models produce germicidal UVC Band light rays, which sterilize and reduce airborne
microorganisms and reduce Volatile Organic Compounds (VOC’s) by a photocatalytic chemical reaction as
air passes through a heating or air conditioning system. It is installed in the main supply or return duct and
operates continuously to automatically purify the air in the home 24 hours a day.
This product is not sold as a medical device and is not for the purpose of diagnosis of any disease or
condition, nor for use in the mitigation, treatment, or prevention of any disease or condition.
READ THESE INSTRUCTIONS CAREFULLY AND COMPLETELY
BEFORE PROCEEDING WITH THE INSTALLATION.
WARNING: For use with 24V ONLY! Do not exceed voltage rating. Severe damage to device and or re
could result. Verify proper voltage.
This product is not sold as a medical device and is not for the purpose of diagnosis of any disease or condition nor for
use in the mitigation, treatment, or prevention of any disease or condition.
READ THESE INSTRUCTIONS CAREFULLY AND COMPLETELY BEFORE PROCEEDING WITH THE INSTALLATION.
This device MUST be installed by a quali ed agency in accordance with the manufacturer's installation instructions. The de nition of
a quali ed agency is: any individual, rm, corporation or company which either in person or through a representative is engaged
in, and is responsible for, the installation and operation of HVAC appliances, who is experienced in such work, familiar with all the
precautions required, and has complied with all the requirements of the authority having jurisdiction.
Please retain these instructions after installation.
Installed By: Phone:
Installation Date:
www. eldcontrols.com

SAFETY CONSIDERATIONS
WARNING: Never expose eyes or skin to UVC light from any source.
• Looking directly at the UVC light may cause permanent eye damage or blindness.
• Never operate the UV-Aire Air Purifying System out of the plenum.
• Designed for a closed duct system. Do not mount near a supply or a return air opening.
• All duct openings in direct line of site of the UV light must be sealed with aluminum tape or equivalent
sealing methods.
WARNING: UV light will break down plastic materials not rated for UV exposure:
(Examples: wire insulation, ex duct, drain pans and humidi ers)
• The unit must be mounted at least 30" from the above stated type of materials.
• If it is necessary to mount the unit in direct line of site of these types of materials, they must be
shielded with aluminum foil, aluminum foil tape, or sheet metal.
WARNING: DO NOT mount this unit outdoors.
• This product is designed for indoor installation only (i.e. attics, crawl spaces, basements, etc.).
WARNING: Never touch broken lamp or internal contents of lamp. The lamp contains mercury.
• After opening the carton, unpack and inspect the unit and lamp for damage. Do not install this unit
if any damage is noticeable. If lamp is damaged, cracked or broken, do not touch lamp or other
contents in carton. Close carton and return to seller immediately.
• In case of accidental exposure to internal contents of lamp, wash hands and any other a ected
skin area with mild detergent. Remove a ected clothing immediately. If skin surface is pierced, seek
medical attention immediately.
NOTE: If you touch the glass of the lamp, you should wipe the glass clean with isopropyl alcohol and
a lint free wipe. If the lamp is not cleaned, the lm of hand oils causes a reduction in the light intensity.
WARNING: Before installing or servicing a humidi er, air lter, HVAC system, or this unit, etc., always turn all
power OFF and have unit unplugged. Electrical shock can cause personal injury or death. Never expose eyes
or skin to direct UVC light from any source.
WARNING: To prevent water damage or electric shock, do not mount unit under a humidi er.
WARNING: This product is designed for indoor installation only (i.e. attics, crawl spaces, basements,
etc.). For use on gas red, oil red, electric and split system heat pump forced air systems.* This
product is NOT designed to be mounted outside on gas red or heat pump packaged units.**
*Split system heat pumps are systems where the air handler and the air conditioning compressor are
separate units.
**Packaged units are systems where the air handler and the air conditioning compressor are built
together and are installed outside of the building.
GENERAL INFORMATION
The UV-Aire unit uses technology that is recommended by doctors who state that "ultraviolet radiation, properly
integrated with heating, ventilating, and air conditioning systems, shows the most promise as a widely applicable
means of air disinfection".
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WARNING: Never expose eyes or skin to UVC light from any source. Looking directly at the UVC light may cause permanent eye damage
or blindness.Never operate the UV-Aire™ Air Purifying System out of the plenum. Avoid touching the glass portion of the lamp with your hands.
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INSTALLATION:
1. Choose a location for the Duo unit, with the following considerations:
a. The Duo unit will reduce organic buildup on an HVAC cooling/
heating coil by illumination with UVC germicidal rays. Locate
the Duo such that the maximum surface area of the coil is
illuminated, while installing as close to the coil as possible
without damage to the coil.
CAUTION: Use care to avoid damage to the coil and any wiring or other components while installing the
Duo 24V unit.
b. The Duo 24V unit must be installed with its power cable within reach of the included 24V
transformer, or the 24V power cable must be extended by using minimal 18 gauge wiring suitable for the
installation, with maximum extension length of 20 feet. DO NOT connect to the HVAC system
transformer, as this may overload the HVAC transformer and/or under-power the Duo 24V
unit, which may cause damage and will void the factory warranty. The included transformer is i
intended to be mounted on a 4x4 junction/conduit box or within an approved electrical enclosure. The
provided 24V transformer shall be connected to 115 or 230 VAC power.
c. The Duo 24V unit may be installed on either the supply or return plenum.
d. The Duo 24V unit may be installed in up ow, down ow, or horizontal ow ducts and plenums.
e. The Duo 24V unit may be installed directly onto a sheet metal air duct or plenum, or onto
berglass ductboard when installed using the included Ductboard Adapter Plate (see Figure 1).
2. Install the Duo 24V unit:
a. Hold or temporarily tape the included Ductboard Adapter Plate in the location chosen for
installation, and using the plate as a template, mark the mounting surface using the outermost
slots in the plate (see Figure 1). Alternatively, a 5-3/8” square may be marked on the mounting
surface.
b. Cut out the opening for the Duo unit in the mounting
surface, making sure to cut slightly outside the marked
lines if the Ductboard Adapter Plate was used as a template.
c. If mounting the Duo unit on ductboard: attach the Ductboard
Adapter Plate to the opening by folding the inner aps of the
plate into the opening and fully back against the inside of the
opening in the ductboard, either from the sides or from top
and bottom of the plate. Finish the Plate Adapter installation
by sealing around the edges of the plate to the ductboard,
using mastic foil tape or other material suitable for sealing
duct joints.
d. If the direction of air ow in the duct is downward, the white
plastic ballast base that is attached to the Duo unit may
Figure 1
optionally be rotated 180 degrees from the position shown, so
the ballast label will not be upside down. If desired, remove the four screws attaching the base
to the Duo unit and re-install the base to the unit. Note: The white plastic base has a round sight
glass hole for observing the lamp inside the duct (the sight glass may be seen above the center
hole in the mounting base in Figure 2). There is a pair of holes in the Duo mounting ange that
allow the sight glass in the base to align with, in either position.glass may be seen above the
center hole in the mounting base in Figure 2). There is a pair of holes in the Duo mounting ange
that allow the sight glass in the base to align with it, in either position.
WARNING: Never expose eyes or skin to UVC light from any source. Looking directly at the UVC light may cause permanent eye damage
or blindness.Never operate the UV-Aire™ Air Purifying System out of the plenum. Avoid touching the glass portion of the lamp with your hands.
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