HVAC School - For Techs, By Techs

Latest Episodes:

Saturation can be CONFUSING - Short #159 Apr 11, 2023

Show notes

In this short podcast episode, Bryan explains why saturation can be CONFUSING and clears up some common misconceptions.

Saturation applies to dehumidification and refrigerant inside the system. Generally, saturation is the state at which a substance can no longer hold or absorb any more of another substance. When air is saturated with water vapor and can hold no more, it is at the dew point or 100% relative humidity; it will condense on any surface below the air temperature.

Air isn't like a sponge that absorbs water vapor; saturation deals with vapor pressure, particularly the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases in a closed system.

Dehumidification is the process by which we remove moisture from the air; this process improves comfort across a significant portion of North America during the summer months, and it prevents fungal growth inside the home. Air in a dehumidifier or an HVAC system in cool mode makes contact with a surface at a temperature below the dew point. So, moisture comes out of the air and condenses on the coil. Colder evaporator coils, which result from longer runtimes, are more effective at removing moisture.

Inside a system, the refrigerant in the evaporator boils as it absorbs heat. The refrigerant can absorb a lot of heat due to the heat required to change state, also known as latent heat (compared to sensible heat, which is the heat required to raise the temperature of a substance). Until the refrigerant completely boils off, it is at saturation. Pressure also dictates the saturation point, and we use refrigerants that can boil under the appropriate temperature and pressure conditions for the HVAC equipment we're working with.

Learn more about the HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

Working on Ventilation in Humid Climates w/ HAVEN Mar 30, 2023

Show notes

Kevin Hart from HAVEN returns to the podcast to talk about ventilation in humid climates and some best practices for working on systems that focus on the V in HVAC. HAVEN focuses on IAQ management with the use of software technology.

HAVEN started off with its central air monitor, and the company then developed a central air controller to help customers make their homes healthier. Fresh-air ventilation is one IAQ, but humid climates make it tricky to bring that air in; dumping "fresh" air into the structure without taking extra precautions can lead to high indoor humidity and even microbial growth.

ERVs, HRVs, and ventilating dehumidifiers are some traditional ventilation strategies for various climates; exhaust ventilation is also quite common but can pull hot, humid air through the building envelope. HAVEN is creating a more templated approach to ventilation; HAVEN uses whole-home in-duct monitoring and local weather data to get ideas of the conditions inside and outside the home to tailor fresh-air ventilation to each individual system's needs.

HAVEN has partnered with several ventilating dehumidifier manufacturers, including Santa Fe and AprilAire; many of these manufacturers also use filtration to control the quality of incoming fresh air.

Kevin and Bryan also discuss:

HAVEN's journey during the COVID-19 pandemic
Chemical interactions in our homes (VOCs and CO2)
Exfiltration and infiltration
The problem with industry standards and regulations
Appropriate climates for ERVs, HRVs, and ventilating dehumidifiers
Using dew point to control indoor and outdoor parameters
Energy savings with HAVEN's technology
Does a house need to "breathe?"
HAVEN app

You can learn more about HAVEN's offerings for HVAC professionals at https://pro.haveniaq.com/ and get a discount on HAVEN's product bundle at https://www.trutechtools.com/ by using the coupon code haven2022.

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

HVAC Performance Summit w/ Dominick G. Mar 23, 2023

Show notes

Dominick Guarino from NCI joins the podcast to talk about the High-Performance HVAC Summit, an upcoming event hosted by NCI from April 17–20. The National Comfort Institute (NCI) is a training organization that helps technicians learn crucial skills and succeed through high-performance contracting.

High-performance contracting is based on the mindset of "don't just promise performance; prove it." To maximize technicians' potential, NCI teaches technicians how to test equipment properly and monetize their skills. Techs can then use their knowledge to teach the homeowner about the system and solve problems with sales; they can earn money while being solutions-oriented.

NCI's High-Performance HVAC Summit is a training event geared toward HVAC business owners and contractors. It started as a membership conference for education and networking, and it has since expanded to include like-minded HVAC professionals from all walks of life. Workshops are led by a mix of contractors and NCI staff, and there are breakout sessions and other various session types.

This year's High-Performance Summit theme will be "It All Starts With Service." The four focal points of the workshops will be lead generation through service and maintenance, CO safety, the lead handoff from service to sales, and maintenance agreements. One more session will focus on hands-on testing, called "Low-Performance Town" this year, and there will be a panel about the future of high-performance HVAC.

Dominick and Bryan also discuss:

Dominick and NCI's history in the industry
High-performance maintenance
Consumers who do their research
The HVACR Training Symposium
High-Performance Summit Awards Banquet
NCI's collaboration with other industry leaders and organizations

Visit https://www.gotosummit.com/ to learn more about the High-Performance Summit. If you decide to register for the summit, type HVACSCHOOL in the coupon code section for a $100 discount.

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

Training, Combustion and More w/ Tony G. Mar 14, 2023

Show notes

In this podcast from AHR 2023, Tony Gonzalez from Fieldpiece joins Bryan to talk about training, combustion, and more.

Fieldpiece has a new combustion analyzer that reduces the cost of tool ownership and maximizes the tool's uptime, namely by using a long-lasting sensor. The combustion analyzer's oxygen and CO sensors seal up when the combustion analyzer is turned off, which pauses degradation. The sensors are also field-replaceable and come with a 4-year warranty. The CAT85 also has a built-in dual-port manometer (which can measure static pressure) and can measure a live draft pressure during combustion analysis.

Some common misconceptions exist around combustion analyzer sensor lifespans and calibration. The sensor life refers to how long a sensor can output a signal to generate a reading; it doesn't refer to the accuracy of the sensor at the end of its life. Calibration keeps the sensors accurate, especially because sensor accuracy tends to degrade over time. To get the most out of your sensor, yearly calibration is recommended.

Fieldpiece is also launching its ambassador program, which is a network of independent trainers with field knowledge who have been trained to become Fieldpiece product experts. Those ambassadors then train contractors and technicians on behalf of Fieldpiece.

Tony and Bryan also discuss:

Fieldpiece's sensor calibration process
Water freezing in combustion analyzer traps
Distinguishing your company from the competition with superior tools
Technical training from Fieldpiece
Fieldpiece leak detectors and new A2L refrigerants
Infrared vs. heated diode leak detector sensors

Learn more about Fieldpiece tools at https://www.fieldpiece.com/ or ask about training by emailing training@fieldpiece.com.

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

The Future of Refrigerants is Here With Opteon XL41 Mar 09, 2023

Show notes

In this podcast from AHR 2023, Brandon Marshall from Chemours and Chris Forth from JCI talk about the future of refrigerants and Opteon XL41 (R-454B).

Refrigerant regulations are changing to pave the way for lower-GWP refrigerants, but M1 is also in full swing. M1 refers to the U.S. Department of Energy's implementation of the new efficiency standards for A/C units and heat pumps (SEER2, EER2, etc.). These standards changed the equipment testing procedure to match field conditions more closely.

Opteon is the next-generation portfolio of low-GWP refrigerants for Chemours as a successor to the legacy refrigerants in the Freon product line. These refrigerants are a response to the HFC phasedown outlined in the AIM Act. JCI chose to use Opteon XL41, an HFO, for its equipment due to Opteon XL41's low GWP compared to R-32 and because of the similar operating pressures and temperatures to R-410A.

A2Ls are a permanent change in the industry, and their safety considerations and best practices are here to stay. However, even though A2Ls are more flammable than A1 refrigerants, they are nowhere near as flammable as A3 refrigerants. Just about any refrigerant can propagate flame under the right conditions (including A1s), so A2Ls are only a little bit more flammable than those.

Brandon, Chris, and Bryan also discuss:

Brandon and Chris's industry experience
The transition from CFCs to HCFCs to HFCs
Refrigerant reclamation
Upcoming GWP limits
Hydrofluoroolefins (HFOs)
A2L refrigerant product testing
Staying up to date on A2L training resources
Some of the prominent flammable refrigerant trainers
Smuggled and counterfeit refrigerants

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

MeasureQuick is EXPLODING with Jim & Joe Mar 07, 2023

Show notes

In this podcast from AHR 2023, Jim Bergmann and Joe Medosch talk about measureQuick and the ways it's EXPLODING with growth and new features. They also talk about heat pumps, electrification, and other hot topics in the industry.

Jim Bergmann recently released an open letter about heat pumps on LinkedIn; he addressed the shortcomings of the industry from a skill standpoint. The lack of training and standards may be mitigated with proper training (and an understanding of building science fundamentals) or by embracing hybrid systems. Heat pumps may also perform relatively poorly during extreme weather events and may not manage temperature swings well.

MeasureQuick has recently been working with ACCA and formed other partnerships to allow for standardization (for companies and the industry as a whole). More companies are also integrating with measureQuick, especially TEC and their TrueFlow Grid; accuracy across brands tends to be pretty consistent, and measureQuick allows you to mix and match tools. The customer-facing side of measureQuick has also received some development, which allows the customer to see the value and quality of their installation.

MeasureQuick is keeping up with the growing pains by doing constant testing. Joe and Jim make sure the user experience is seamless, intuitive, and free of problems or inconveniences.

Jim, Joe, and Bryan also discuss:

Fixing the building envelope
Heat pump vs. gas furnace comfort
Energy Star certification for installations
measureQuick user base milestones
Industry leaders, supporters, and partnerships
New measureQuick workflows
Joe Medosch's role at measureQuick
The challenges of the HVAC trade
Technology challenges for measureQuick's users
Free and paid measureQuick features

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

Infiltration Skeletons Behind Closed Doors w/ Genry Mar 02, 2023

Show notes

Genry Garcia returns to the podcast to talk about pressures in the building envelope, namely the infiltration skeletons behind closed doors.

When doing load calculations (Manual J), we need to know how much of the heat load, especially the latent heat load, comes from leakage in the building envelope and the ducts. Opening/closing doors and windows can also worsen the issues that stem from infiltration due to upsetting the balance of pressures in the home. Smoke pencils and other similar tools can give you an idea of the pressure in a home and how it could change when doors open or close.

Since there is a lot of room for inaccuracy in extreme climates (especially those with high latent loads), many HVAC systems are oversized and underperform. Some building design features also exacerbate problems presented by oversized HVAC systems. To get the data we need to design systems that mitigate those issues, we need to do a blower door test.

Downsizing the tonnage in retrofits or replacements usually has advantages, but it must be done right, and customers may not always want to do that. It's the contractor's responsibility to give them a choice and educate them about the options and what the thorough diagnostic process looks like, including balancing the home and checking the pressure in relation to the outdoors.

Genry and Bryan also discuss:

Positive and negative pressure in certain rooms
Exhaust ventilation and pressurization
Using See Stack to see differences in loads
Leaving the fan in the "on" position
Useful tools
Variables in lab-based testing and field testing
Getting hung up on the 3 Pascals rule of thumb
Leaky rooms vs. whole-home leakage

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

Understanding Leak Detectors With Inficon Feb 28, 2023

Show notes

In this episode recorded live at AHR Expo 2023, Nick from INFICON joins Bryan to talk about leak detectors and how we can improve our understanding of them.

Some leak detectors, including the INFICON Stratus, measure concentrations in PPM (parts per million). When measuring PPM, we have to keep in mind that it doesn't indicate the size of the leak or leak rate, but it does help us pinpoint the leak location. In some cases, we also have to watch for automatic zeroing capabilities.

Leak detectors come in many varieties, including heated-diode, ultrasonic, and infrared; each type has unique maintenance needs. Heated-diode leak detectors are sensitive, but their sensors wear off with frequent use and will require replacement. Infrared leak detectors use infrared absorption and don't degrade over time the way heated-diode leak detectors do. An ultrasonic leak detector picks up the sound of refrigerant and air leaking out of a hole to pinpoint the leak.

It's a good idea to approach leak detection with a plan, including starting high on the coil and moving down (because refrigerant is heavier than air and may set off the leak detector below the actual leak). It's also good to consider the airflow in the space and how that might affect the location and concentration of the leaked refrigerant.

Nick and Bryan also discuss:

Pressure, hole shape, and leak rate
Understanding tool maintenance
Infrared leak detector usage and considerations
Common causes of leak detector failure
D-TEK product line
CO2 and hydrocarbon sensors for leak detectors
D-TEK Stratus modes (cloud hunting and pinpoint)
Applications for D-TEK Stratus leak detectors
"False" positives

Learn more about INFICON at https://www.inficon.com/.

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

Making Cold Climate Heat Pumps Work w/ Copeland and White Rodgers Feb 23, 2023

Show notes

In this episode recorded live at AHR Expo 2023, Dustin and Jim from Copeland/White-Rodgers join Bryan to talk about the use of heat pumps in cold climates. They talk about the history of heat pump innovation and talk about changes to come.

Variable-speed and two-stage compressors, as well as advanced controls, make it easier for contractors to control sizing and for heat pumps to perform to acceptable standards in cooler climates. Contractors in cold climates also rely on dual-fuel models that use electric and gas heat, which makes it easier for the system to move the desired amount of heat.

Variable-speed and two-stage compressors help the system deal with different heating and cooling capacities; in cooling mode, these technologies can also help with latent removal if the blower is also able to vary with the compressor.

Advanced controls, especially universal controls, also help with defrost management, a key component of heat pump performance. When defrost is managed effectively, customers can yield energy savings. The White-Rodgers universal defrost control comes with coil and outdoor temperature sensors (thermistors) to determine when the unit is ice-bound; it also has a thermostat that can control second-stage heat.

Dustin, Jim, and Bryan also discuss:

Electrification and heat pump sales
Vapor injection and compression ratio control
Freq drives
White-Rodgers universality and nomenclature
Timed vs. demand defrost
Electric heat vs. gas/oil heat costs
WR Mobile app
Multi-volt contactors (White-Rodgers SureSwitch)
Pool heat pumps and contactors
Crankcase heaters, long line sets, and total system charge
A2L refrigerant testing

Learn more about White-Rodgers products on the WR Mobile app, our partner page at https://hvacrschool.com/partner/emerson-white-rodgers/, or the website at https://climate.emerson.com/en-us/brands/white-rodgers.

Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

Check out our handy calculators HERE.

RTU Retrofits Facts and Considerations with JCI Feb 21, 2023

Show notes

In this episode recorded live at AHR Expo 2023, Matthew Schlegel, the Commercial Product Manager of Ducted Systems from JCI (Johnson Controls) joins Bryan to talk about rooftop unit (RTU) retrofit facts and considerations.

When doing an RTU retrofit, you want to make sure you know the budget before anything else; larger budgets will allow you to implement things like VFDs and even VAV technology. In many cases, you may consider adding an economizer for "free" cooling and energy savings. You also want to know what you will get out of a retrofit in terms of value, especially when it comes to system efficiency and longevity.

Some common IAQ upgrades for RTUs include improved filtration, especially with MERV 13 filters. Economizers also allow you to control the amount of outside air with the help of an exhaust system or even barometric relief. UV lighting can also be used in light commercial RTUs.

When doing a retrofit, you'll want to pay attention to the existing equipment's footprint. Sticking to that footprint will make the replacement aspect easier. The utility and electrical infrastructure are also important to consider, as you won't want to replace the existing piping, wiring, and connections.

With regulations and technology constantly changing, it helps to be able to contact the manufacturer to assist with the retrofit process. Companies like JCI are trying to assist contractors with installations by providing guidance and education in the field.

Matthew and Bryan also discuss: