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  • Patented self-cleaning design ensures ongoing peak performance
  • Needlepoint ionization actively treats air in the living space
  • External mount install for systems up to 12 tons (4800 CFM)
  • Meet’s UL 2998 Zero Ozone Emission Certification
  • No maintenance for the life of the NuShield
  • Easily installs in any ducted HVAC system
  • Patented multi-voltage input – 24VAC to 240VAC
  • Flexible design with no replacement parts
  • Reduces certain bacteria and viruses*
  • Reduces odors, smoke and other airborne particles
  • Keeps coil cleaner longer
  • Integral alarm contact for remote monitoring
  • UL and cUL certified
  • CARB certified
  • Three-year limited warranty


NuShield-CX is a self-cleaning, bi-polar ionization generator for actively treating a building’s air quality that does not require replacement parts in a year or two like competing UV lights or other ionizer technologies. In addition, the NuShield-CX produces and maintains unparalleled ionization output and capabilities. As the air flows past the NuShield-CX, the device emits positive and negative ions that actively treat the supply air, reducing certain bacteria and viruses* in the coil and living space. The ionization process also reduces smoke, odors (cooking, pet, VOCs), as well as other particles (no more sunbeams) in the air. NuShield meets UL 2998 zero ozone emission certification.

Although suitable for residential applications, the NuShield-CX is specially designed for light commercial systems up to 12 tons (4800 CFM) with no maintenance or replacement parts needed. NuShield-CX can be easily externally mounted in any ducted HVAC system. NuShield-CX always works at peak performance, producing over 200 millions ions/cc per polarity (400 million total ions/ cc), making it superior to other market approaches. The NuShield-CX includes a self-cleaning cycle, integral alarm contact (for remote monitoring), and patented multi-voltage input.

Three Year Limited Warranty Nu-Calgon offers a three year limited warranty on NuShield products. For a valid warranty claim within three years, proof of purchase and proof of installation by a licensed HVAC or Electrical contractor must be provided. See full warranty at for complete details.

DISCLAIMER: NuShield uses multiple data points to formulate performance validation statements. NuShield technology is used in a wide range of applications across diverse environmental conditions. Since locations will vary, clients should evaluate their individual application and environmental conditions when making an assessment regarding the technology’s potential benefits.

The use of this technology is not intended to take the place of reasonable precautions to prevent the transmission of disease. It is important to comply with all applicable public health laws and guidelines issued by federal, state, and local governments and health authorities as well as official guidance published by the Centers for Disease Control and Prevention (CDC), including but not limited to social distancing, hand hygiene, cough etiquette, and the use of face masks.

* See Performance Data at

Packaging Size Part Number Additional Info
NuShield-CX 4900-55 Commercial External Installation


Nu-Calgon recommends mounting the NuShield-CX downstream of the last filter in the HVAC system. Alternate mounting locations are on the supply air duct or the return air duct after the filter.  The duct must have a depth greater than 8 inches for the unit to  operate properly. The weatherproof housing will allow mounting indoors or out.
NOTE: Use Temperature - Maximum ambient temperature in which unit shall be used: 140ºF / 60ºC.

Mechanical Installation
1. Ensure power to the HVAC equipment and the NuShield-CX has been disconnected.
2. Find an appropriate location. Verify the 8-inch depth clearance for the NuShield-CX.
3. Cut a 4-inch round hole in the duct.
4. Install the NuShield-CX so that airflow is passing by both emitters at the same time in line with the airflow indicator on the product.
The conduit and connection grommet should be pointed down or to the side. Secure to the duct with provided screws.

1. Confirm the power is off prior to wiring. Follow all local and national electrical and building codes.
2. Nu-Calgon recommends the NuShield-CX be powered constantly but it may be switched with the system or blower.
3. The NuShield-CX will self-adjust to voltages from 24VAC to 240VAC. Output and performance will not be affected by choice of input
voltage. Connect the power wires as follows:
Black = 24 - 240VAC
White = Neutral or L2
Green = Ground
Brown = Dry Contacts/BAS Alarm
4. Wire in BAS terminals (optional). The NuShield-CX is equipped with dry contacts that are normally open and close when the NuShield-CX
is on and has no faults. The contacts are rated up to 250VAC and 1A.

Once powered, the unit initiates an internal check of all systems. If the auto cleaning wiper blade is not in the “home” position, it will move
to the home position in series with the airflow and a green LED on the NuShield-CX will illuminate.

Cleaning Cycle
The NuShield-CX comes with a factory preset cleaning cycle designed to clean the emitters once per day.

1. Unit will not power up, no display:
a. Confirm proper voltage is applied to the correct terminal(s).
b. Try an alternate power source. If using 24v try using 120v or vice versa.
2. If unit does not operate properly after verifying the above instructions please contact Nu-Calgon for additional assistance.
3. If unit does not operate properly after verifying the above instructions
a. Contact Nu-Calgon for additional assistance.

Product Information:

Literature Downloads

Download the product bulletin and other relevant literature here.


Download a low resolution file of the product label here.

Product Safety

RTK Information

2611 Schuetz Rd. St. Louis, MO 63043
  • Telephone: 800.554.5499
  • Email: [email protected]
  • Hours: Mon–Fri: 8:00am - 5:00pm (Central Time)

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