Refrigeration Frost vs Ice Truths for HVAC Techs to Prevent System Failure - Julian Finbow Part 1

In this episode of the HVAC Know It All Podcast, host Gary McCreadie is joined by Julian Finbow, RSE, Service Tech Support at Swegon North America, and Principal at Finbow Inc., to discuss refrigeration defrost methods and why they are essential for system performance. Julian explains how frost forms on evaporator coils, the difference between normal frost and ice buildup, and why proper defrost timing is important. The conversation covers common defrost methods such as hot gas, electric, off cycle, and off time defrost, along with how humidity, door openings, and evaporator placement affect frost buildup. Gary and Julian also explore hot gas defrost, its benefits, its challenges, and why proper system design and operation are critical for reliable refrigeration performance.

In this conversation, Julian explains why defrost is needed in refrigeration systems and how frost forms on evaporator coils when they operate below freezing temperatures. He discusses the difference between normal frost, hoar frost, and ice buildup, and why proper defrost timing is important for good system performance. Julian and Gary explore topics such as off cycle, off time, electric, cool gas, and hot gas defrost, along with how humidity, door openings, and evaporator placement affect frost buildup. They also discuss how hot gas defrost works, its benefits and challenges, and why proper system design and defrost settings help keep refrigeration systems running efficiently.

Expect to Learn:

• Why defrost is needed in refrigeration systems and how frost forms on evaporator coils.

• The difference between hoar frost, normal frost, and ice buildup, and why it matters.

• How off cycle, off time, electric, cool gas, and hot gas defrost methods work.

• How humidity, door openings, and evaporator placement affect frost buildup and defrost needs.

• The benefits and challenges of hot gas defrost, and why proper defrost timing improves system performance.

Episode Highlights:

[00:00] - Sponsor Ad: Factory Direct Filters

[00:42] - Intro to Julian Finbow, RSE in Part 1

[02:37] - Recap of Ammonia Plant Tour & Social Media Success

[04:12] - Julian's Background & Expertise

[05:48] - Defining Defrost in Refrigeration vs. Heat Pumps

[08:02] - Normal Frost vs. Problematic Ice on Coils

[10:55] - Standard Defrost Cycles: 4 Times a Day

[16:10] - Defrost on Walk-in Coolers & Mitigation Strategies

[18:26] - 5 Main Types of Defrost Explained

[21:33] - How Hot Gas Defrost Works (Pros & Cons)

This Episode is Kindly Sponsored by:

Cintas: https://www.cintas.com/hvacknowitall

Cool Air Products: https://www.coolairproducts.net/

Factory Direct Filters: https://www.factorydirectfilters.com/

SupplyHouse: https://www.supplyhouse.com/tm
Use promo code HKIA5 to get 5% off your first order at Supplyhouse!

Follow the Guest Julian Finbow, RSE on:

LinkedIn Profile: https://www.linkedin.com/in/julian-finbow-rse-1048038b/

LinkedIn - Swegon North America: https://www.linkedin.com/company/swegon-north-america/

LinkedIn - Finbow Inc.: https://www.linkedin.com/company/finbow-inc/

Website - Swegon North America: http://www.swegonnorthamerica.com/


Follow the Host on:

LinkedIn: https://www.linkedin.com/in/gary-mccreadie-38217a77/

Website: https://www.hvacknowitall.com

Facebook: https://www.facebook.com/people/HVAC-Know-It-All-2/61569643061429/

Instagram: https://www.instagram.com/hvacknowitall1/

Follow the Podcast on:

YouTube: https://www.youtube.com/@HVACKnowItAll

Spotify: https://open.spotify.com/show/6LCBJGw0EHG03rdWHxUMce

Apple Podcast: https://podcasts.apple.com/us/podcast/hvac-know-it-all-podcast/id1359253455