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#copeland mobile

Tech Tips:

Scroll Compressors in a Changing Regulatory Landscape

This tech tip is based on an HVAC School podcast episode about scroll compressors and new refrigerants with Jeff Kukert and Tom Fesenmyer from Copeland. Jeff is the senior technical trainer, and Tom is the manager of technical services. You can listen to the original podcast HERE, and you can explore Copeland’s vast selection of […]

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Users with Tag #copeland mobile

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How to Evacuate an AC system, Full Vacuum Procedure

Our latest Podcast

HVAC School – For Techs, By Techs

HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

VRF, Ductless and Humidity Control w/ Roman

byBryan Orr

In this comprehensive episode, Bryan and Roman dive deep into one of the most challenging topics in modern HVAC: making VRF (Variable Refrigerant Flow) and ductless systems perform effectively in humid climates like Florida. The conversation tackles a common misconception that inverter-driven equipment automatically handles humidity well simply because it can “turn down.” Roman emphasizes that successful application of VRF technology in humid environments requires skilled professionals who understand building science, envelope integrity, and proper system sizing. The biggest takeaway? If you’re going to err on sizing, undersize rather than oversize – these systems will run longer and maintain better humidity control when properly sized.

The hosts explore the three critical factors for dehumidification: runtime, coil temperature, and surface condensation. They explain how traditional inverter systems were programmed for energy efficiency by allowing coils to warm up as they approached the set point, which unfortunately sacrifices latent capacity. Modern systems with active dehumidification capabilities use expansion valve control to “starve” the coil, lowering saturation temperature to around 35-37 degrees while extending runtime. Roman shares his personal experience with a 7,000 BTU unit serving his 700 square foot master bedroom suite, demonstrating how proper application and understanding of equipment capabilities can deliver excellent humidity control without oversizing.

The discussion takes a practical turn as Bryan presents a comprehensive troubleshooting checklist for humidity problems, starting with bulk water leaks and progressing through envelope integrity, duct sealing, equipment selection, and pressure balancing. They debunk common “solutions” that actually make problems worse, like adding attic insulation or solar attic fans without addressing root causes. The conversation reveals a counterintuitive truth: reducing sensible load through excessive insulation can worsen humidity problems by reducing equipment runtime. They explain why “active dehumidification” through overcooling isn’t true dehumidification, and why another solution – reheat – requires adding sensible heat back to spaces to maintain longer equipment runtime.

Topics Covered:

VRF and inverter sizing misconceptions – Why undersizing is often better than oversizing in humid climates
Three factors of dehumidification – Runtime, coil temperature, and surface condensation explained
Active dehumidification technology – How expansion valve control creates longer runtime and colder coils
Equipment capacity ratings – Understanding that a “12K” unit may actually perform at 18,000 BTU
Latent vs. sensible capacity – Why checking engineering specifications is critical for humid climate applications
VRT (Variable Refrigerant Temperature) – When this energy-saving feature should be disabled in humid climates
Fan operation strategies – Why continuous fan operation can worsen humidity problems
Duct and envelope leakage – How pressure imbalances drive moisture problems
Surface condensation – Why vents and ducts sweat and how to prevent it
The overcooling trap – Why lowering the set point creates interstitial space moisture problems
Humidity sensors in thermostats – Understanding what they do (and don’t do)
Load diversity and zone control – How multiple smaller units can outperform single large systems
Reheat strategies – From electric resistance to passive solar gain
Common mistakes – Why attic insulation and solar fans often worsen humidity issues
Troubleshooting checklist – A systematic approach from bulk water to equipment selection

Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.

Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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VRF, Ductless and Humidity Control w/ Roman

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VRF, Ductless and Humidity Control w/ Roman

11/27/2025

Bryan Orr

The History of the Thermostat – Short #267

11/25/2025

Bryan Orr

Tech Support Highs and Woes w/ Roman

11/20/2025

Bryan Orr

The Current War – Tesla, Edison & Westinghouse – Short #266

11/18/2025

Bryan Orr

An R-454B Ramble w/ Elliot

11/13/2025

Bryan Orr

Psychrometrics and the Magic Line – Short #265

11/11/2025

Bryan Orr

Learning Hydronics, Boilers and Steam w/ Ray Wohlfarth

11/06/2025

Bryan Orr

How Duct Tape Got Its Name (and Why It Shouldn’t Be on Ducts) – Short #264

11/04/2025

Bryan Orr

The Art of De-escalation

10/30/2025

Bryan Orr

Legionnaires’ Disease: The Cooling Tower Killer – Halloween Short #263

10/28/2025

Bryan Orr

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Check our latest Tech Tips

Set Inverter Technology Up for Success in Humid Climates Why Airplanes Fog Up Before Takeoff Why the Sauna Feels Hotter When You Throw Water on the Rocks

VIPER SNIPER UNIVERSAL AEROSOL TRIGGER SPRAYER

VIPER SNIPER UNIVERSAL AEROSOL TRIGGER SPRAYER The Viper Sniper is an ergonomic trigger sprayer that fits all standard aerosol cans. Designed for comfort and control, it reduces finger fatigue and delivers a smooth, consistent spray, especially in those hard-to-reach areas. Features quick-attach side clips for easy, secure use. Compatible with all standard aerosol cans —including Viper Aerosol Coil Cleaner and Coil Coating Spray. Fits Any Aerosol Can Full Hand Ergonomic Grip Easily Clips On and Off 2 Sprayers per pack

VENOM PACK CONDENSER PURE CONCENTRATE COIL CLEANER

VENOM PACK CONDENSER PURE CONCENTRATE COIL CLEANER Venom Pack Condenser Cleaner is a high foaming pure concentrate liquid designed to tackle the toughest soils. The proprietary blend of specialty detergents will liquify heavily embedded grease and grime to restore heat transfer and increase the efficiency of the coil.

Viper Condensate Pan and Drain Treatment

Viper Condensate Pan and Drain Treatment Viper Condensate Pan and Drain Treatment is a sprayable gel. It coats the pan, p-trap and drain piping with a lubricative film to improve flow and prevent future soil adhesion. The slow dissolving enzyme gel will outperform and outlast conventional tablets and strips.

Nylog Blue Gasket -Thread Sealant for AC/R Systems

Nylog Blue Gasket -Thread Sealant for AC/R Systems One drop of Nylog on your rubber hose gaskets prior to attaching your core tools, hoses or vacuum gauge will assure that things do not bind or leak during evacuation. Derived from refrigeration grade lubricants. Non-hardening, non-drying fluid which bonds tenaciously to many different substrates. Typically, one drop of Nylog can be stretched about three feet before breaking.

NAVAC

Find out more about the Innovative NAVAC line of Vacuum Pumps

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