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Bio-Fresh cd

  • A concentrated, ready-to-use bacteriostat that is a fungistat and deodorant
  • EPA registered for application in HVACR systems No. 9804-3-65516
  • Can be sprayed in occupied areas
  • Kills odors and controls bacteria
  • Eliminates odors where they exist


Bio-Fresh cd is a ready-to-use bacteriostat, fungistat and deodorizer based upon chlorine dioxide technology. It is recommended for control of bacteria, mold, mildew, fungi and yeast in IAQ applications. Its EPA registration includes application in HVACR ventilating equipment, including coils, condensate pans, filters and duct-work.

Evaporator coils, condensate drain pans, filters and duct-work in air conditioning systems can be an excellent breeding ground for bacteria and mold. Left untreated, it can grow and eventually affect indoor air quality, a major concern of the IAQ movement today. Use of a product like Bio-Fresh cd in a total program such as Nu-Calgon’s IAQ Assurance Program will correct this problem by inhibiting the growth of bacteria or mold.

NOTE: This product is not registered for sale in Canada.

Packaging Size Part Number Additional Info
1 quart spray bottle 4126-34
1 gallon bottle 4126-38


This product must be used in accordance to the following directions by HVACR professionals only.

For Residential Control of Odors Associated With Bacteria, Mold, Mildew, Animals, Smoke, etc.: Thoroughly spray source of odor with Bio-fresh cd or mist air by squeezing trigger several times. Severe odors may require repeat applications.

To Deodorize HVAC System Duct Work: Fog or spray Bio-fresh cd into system intake vents while system fan is running. Allow enough spray time for Bio-fresh cd to contact air duct system surfaces. Repeat application as necessary. (See directions under the Bio-fresh fogger for further directions.)

For Microbial Control of Evaporator Coils, Drip Pans and Associated Air Conditioning Parts: Air conditioning system parts should be manually pre-cleaned prior to application using a suitable coil/drip pan cleaner. After cleaning, thoroughly spray Bio-Fresh cd onto cleaned surfaces. Do not wipe off. Allow to air dry.

DISCLAIMER: 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.”

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:
  • Hours: Mon–Fri: 8:00am - 5:00pm (Central Time)

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