2024 AHR Expo: Hydronic Snow and Ice Melting System Design to Optimize Performance and Efficiency

Hydronic snow and ice melt (SIM) systems are installed outside under driveways, sidewalks, ramps, stairs, etc., to prevent slips and falls that could cause injury. Many hospitals, schools, senior facilities, and commercial buildings install them for safety – and to reduce liability.

"The safety, convenience, and savings provided by a SIM system are more beneficial than ever, as changing weather patterns increase snowfall in many regions," noted Lance MacNevin, director of engineering in the Plastics Pipe Institute's Building and Construction Division, Jan. 24 at the 2024 AHR Expo in Chicago.

Other relevant issues include:

1. Clearing slippery outdoor surfaces over a long winter is a high maintenance cost and involves the expense of harsh chemicals, which can damage surfaces.
2. Aging populations need access to services, yet may have limited mobility.
3. Snow and ice melting systems can reduce liability while improving access.
4. Operating costs for a hydronic SIM system are often much less than mechanical snow removal, saving facility owners money while reducing risks.

MacNevin listed SIM's benefits:

• Better safety, keeping surfaces clear during snowfall events and evaporating water to prevent freezing;
• Reduced liability as residences and businesses free of snow and ice improve access and safety while eliminating a source of liability risk in winter.
• Healthier convenience, leaving them dry, and eliminating potential health risks of aching backs and heart attacks for homeowners.
• Lowered maintenance costs as hydronic SIM systems are usually less expensive to operate than mechanical removal.
• Minimized environmental impact as hydronic SIM systems are powered by heat sources such as high-efficiency boilers, electricity, thermal solar, geothermal heat pumps, or waste heat.
• Long-term liability as plastic tubing does not corrode on the inside or outside, and hydronic boilers, circulators, and piping components are highly reliable.

He discussed installation techniques and typical applications for SIM, then explained SIM design steps: 

1. Select the appropriate performance level for the customer.
2. Determine the required heat output/heat flux.
3. Select and size heat source to meet the peak load.
4. Design the piping distribution system in terms of size, spacing, and circuit lengths. 
5. Size hydronic equipment such as circulator pumps, expansion tanks, etc.

MacNavin concluded his session by explaining SIM control strategies and operation costs.