ACCA Publishes Tech Bulletin on Anti-Sweat Heaters Used in Refrigeration Food Merchandisers

November 30, 2016

ACCA, the Indoor Environment & Energy Efficiency Association, has published a Technical Bulletin titled, "An Overview on the Types and Function of Anti-Sweat Heaters Used in Refrigeration Food Merchandisers." The new technical bulletin is available to ACCA members to download for free at

Most refrigerated merchandiser manufacturers factory install anti-sweat heaters on refrigerated cases where the conditioned space is intended to operate below 40°F.  A typical supermarket merchandiser is designed, and the load calculations are assumed, to be placed in a store location with ambient air conditions of 75°F Dry Bulb and 55% relative humidity (RH).  This yields a Dew-point of 58°F.  Hence, anti-sweat heaters are installed to maintain case surface temperatures above the Dew-point so as to prevent:

  1. Customers from coming into contact with wet surfaces, and/or
  2. Condensed water from dripping onto the floor, and/or
  3. Water and/or ice from dripping onto products in the refrigerated space. 

This technical bulletin addresses the different types of controls and sensors for anti-sweat heaters and explains the reasons for demand-cycling the heaters vs. continuous-run operation. The Technical Bulletin also offers installation and maintenance guidance as well as guidance for the technician when talking to the store manager relative to energy usage and conservation.

If you have questions or comments about the technical bulletin, email Danny Halel, ACCA Manager of Standards at


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ACCA is a non-profit association serving more than 60,000 professionals and 4,000 businesses in the indoor environment and energy services community. Our member firms are the nation's most professional contracting businesses, serving residential and commercial customers in every state. With roots stretching back a century, ACCA was incorporated in its present form nearly 50 years ago. Today, ACCA sets the standards for quality comfort systems, provides leading-edge education for contractors and their employees, and fights for the interests of professional contractors throughout the nation. Learn more about ACCA here.