HVAC School - For Techs, By Techs

Latest Episodes:

An ACCA Form You Probably Never Heard Of w/ Ed J. Jan 04, 2024

Show notes

The podcast is a conversation between Ed and Bryan about using the ACCA Residential Plans Examiner Review Form, an ACCA form you probably never heard of, to demonstrate that proper HVAC system design procedures were followed based on the Manual J, Manual S, and Manual D guidelines.

Ed introduces the Residential Plans Examiner Review Form as a one-page document that allows contractors to show they gathered the minimum necessary information to complete a proper HVAC system design. The form doesn't teach how to actually do the design calculations but can help explain the design to others not familiar with it, like code officials asking for documentation. The form is meant as a bridge to facilitate communication between contractors and authorities having jurisdiction (AHJs). Ed shares stories of using the form successfully to work with code officials and gain approval.

Bryan asks clarifying questions about the intended audience for the form - whether for residential new construction only or also replacement - since it references the duct design Manual D procedures. Ed explains the full manuals would likely only apply to new construction and add-ons, but elements could apply to replacements if load calculations are required locally. The details depend on the specific project and jurisdiction.

Topics covered:

Purpose and use of ACCA Residential Plans Examiner Review Form
Information that the form documents from Manual J, Manual S, and Manual D
The form's audience (primarily code officials/AHJs, but it's also helpful for contractors)
Applicability for residential new construction, add-ons, and some replacements
Stories of working with local code officials using the standard form
Where to access online - ACCA website and search by full name

Access the document information and examples online HERE and learn more about ACCA at https://acca.org/home.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

Solving & Preventing Oil Issues in Rack Refrigeration Dec 28, 2023

Show notes

In this HVAC podcast episode, hosts Bryan Orr and Matthew Taylor (refrigeration leader and trainer at Kalos Services) discuss oil management and considerations in supermarket refrigeration systems, with a focus on solving & preventing oil issues. They talk about the importance of stable system operation and how oil flows through both active and passive systems in these larger built-up racks.

Matthew explains that in a rack system, oil is actively separated and returned to the compressors through a dedicated system. However, not all oil gets captured this way, so the passive system of oil returning through the refrigeration cycle still occurs. Problems can arise in either system, leading to compressors locking out. Matthew stresses properly setting and regulating EPR valves to minimize load fluctuations that impact system stability.

Common issues covered include clogged oil separators, misadjusted or damaged oil controls, changes in suction pressure affecting oil flow, the impact of floating suction pressures, and troubleshooting overfilled compressors. Matthew offers tips like feeling the oil separator line temperature and using working racks as a guide when unsure of proper settings. The discussion highlights how poor defrost performance can indicate oil trapping issues.

Matthew and Bryan also cover:

Active vs passive oil management in racks
Setting EPR valves for stable operation
Clogged oil separators and failed floats
Suction pressure fluctuations disrupting oil flow
Strategies for floating suction pressures
Steps for readjusting oil controls
Signs of oil trapping issues in the refrigeration cycle
Using working racks to guide troubleshooting

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

What is A2L Mitigation Going to Look Like? w/ Clifton B. Dec 21, 2023

Show notes

In this podcast, Bryan and Clifton discuss the upcoming transition to A2L refrigerants, like R-32 and R-454B, and what A2L mitigation is going to look like.

These mildly flammable refrigerants will be used in place of R-410A for residential air conditioning systems due to an HFC phase-down driven by legislation and international agreements. They explain what mitigation means with A2L systems - sensors will detect refrigerant leaks, and the system will shut off and turn on the blower fan to dissipate any leaked refrigerant. The mitigation helps minimize flammability risk.

They note the new A2L refrigerants contain no propane despite some misconceptions. The fundamentals of safe installation, service, and repair remain similar but will be absolutely required for A2Ls versus more loosely followed with previous refrigerants. Taking proper time and care is crucial. Bryan and Clifton then discuss the education, training, and resources available from ESCO Group to help contractors prepare for this transition.

Key topics covered:

Upcoming transition to A2L refrigerants R-32 and R-454B
Phase down of R-410A driven by legislation and international agreements
Definition and purpose of mitigation used with A2L air conditioners
Misconception that new refrigerants contain propane
Fundamentals of safe installation and service remain similar but even more vital
Taking the proper time and avoiding rushing is crucial for safety
Education, training, and resources available from ESCO Group
Preparing the HVAC industry for the refrigerant transition
The yearly AHR Expo and HVAC Excellence Conference

You can learn more about ESCO Institute at https://www.escogroup.org/ and explore the HVACR Learning Network at https://hvacr.elearn.network/.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

Healthy Air Supplements vs. Pillars w/ Kevin Hart Dec 14, 2023

Show notes

Bryan and Kevin discuss indoor air quality solutions in terms of healthy air supplements vs. pillars of IAQ, drawing an analogy between IAQ supplements like electronic air cleaners and fitness supplements. They talk about why discussing these supplemental products can be controversial since many companies profit from selling them. However, the fundamentals of good IAQ - ventilation, filtration, and humidity control - are proven to work well, just as diet, exercise, and hydration promote good health.

Most contractors focus more conversations and training around supplemental IAQ products versus the fundamentals, which parallels how society embraces fitness supplements over proper diet and exercise. However, a growing group of homeowners want real solutions, and the fundamentals often solve problems better and with less risk than just adding devices. Measuring IAQ and using data-driven diagnoses lead to more targeted solutions, too.

The fitness analogy applies well - you don't jump to supplements first, and adding more supplements isn't always better or healthier. Dosage and application really matter. Contractors should consider focusing 80% on IAQ fundamentals over supplemental products to best serve customers.

Topics covered:

Why discussing IAQ supplements is controversial
Fundamentals of good IAQ: ventilation, filtration, humidity control
Parallels between IAQ supplements and fitness supplements
Reliance on and training around supplemental products versus fundamentals
Growing consumer demand for real IAQ solutions
Using IAQ monitoring and measurement for better solutions
How having more supplements or devices isn't always better
Dosage and proper application really matter
Shifting contractor focus to 80% on IAQ fundamentals versus supplemental products

You can learn more about HAVEN products at https://haveniaq.com/ or become a HAVEN pro at https://pro.haveniaq.com/.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

Hot Deck, Cold Deck - Short #182 Dec 12, 2023

Show notes

In this short episode, Bryan discusses the unique features of hot deck, cold deck systems. These systems have separate heating and cooling components (if not entire systems).

Older systems may have completely separate duct systems: one for heating and one for cooling. These ducts would go to each space, and you'd essentially have twice the ductwork you'd expect nowadays. Some systems also have a separate hot deck and cold deck in a single appliance (a bit like gas furnaces with case coils).

We also use the term "hot deck, cold deck" to refer to systems with secondary fluid in a single appliance that produces heating and cooling. Heat recovery or heat-pump chillers use secondary fluids to carry heat around (these fluids don't expand and change state like refrigerant). A traditional chiller is often used in combination with a boiler system, and both can be shut on or off; this configuration can be tricky in shoulder seasons, and a hot deck, cold deck system could be beneficial instead. Buffer tanks also allow energy to be stored in a hot deck, cold deck configuration.

Hot deck, cold deck systems may also be beneficial in humid climates if the cooling component is before the heating component; the system could provide heating, cooling, and dehumidification. You could also use hot deck, cold deck systems for domestic hot water (via a heat exchanger) and cold plunges. It's even possible to use flammable refrigerants in heat recovery chillers that use this configuration.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

Common Callbacks and Failed Inspections on Install Dec 07, 2023

Show notes

In this episode of HVAC School, hosts Bryan Orr and Bert discuss practical tips for preventing callbacks and failed inspections in residential HVAC installs and maintenance.

Bryan and Bert stress the importance of getting the basics right, like properly cleaning condensate drains, ensuring proper drain pitch, and sealing ducts completely before relying on tapes and mastic to cover gaps. They emphasize verifying full system operation at the end of a job, from checking that drains flow freely to testing float switches and pressure testing for leaks. Bryan and Bert also cover wire and breaker sizing for equipment changes, securing disconnects, proper thermostat wall seals, inspecting joints with bubbles to find microscopic leaks, and more thorough evacuations and leak checks.

Throughout the casual, conversational show, the hosts inject colorful commentary on doing quality work with a little sarcasm, including praising the merits of duct board and flex ducts. The tone is partly tongue-in-cheek but drives home the point that shortcuts lead to callbacks and leave clients dissatisfied.

Bert and Bryan also discuss:

Becoming masters of the obvious
Common condensate line issues
The issues with double traps
Ensuring adequate filter access for the customer
Wiring float switches in series vs. in parallel
Sealing ductwork effectively
Using your senses to find airflow leaks in the ductwork
Pressure testing for refrigerant leaks
Common leak points in systems and their causes
Correct electrical setup and markings
Securing outdoor unit placement
Sealing thermostat wall penetrations
Thorough evacuation and leak checks

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

When Permits Are Not Needed - Short #181 Dec 05, 2023

Show notes

In this short episode, Bryan talks about the situations when permits are not needed to install HVAC/R (or HVAC/R-related) components.

A few codes are universal in residential HVAC, including the International Residential Code (IRC) and the International Mechanical Code (IMC). The local municipality, also known as the authority having jurisdiction (AHJ), chooses which codes to adopt.

You do not need a permit to install plug-in, cord-connected appliances. However, you need UL-listed plugs. You can also replace plugs without needing a permit, but the ratings need to be correct. Anything less than 25v that doesn't put out more than 50 watts of energy also doesn't require a permit. Thermostats and many IAQ accessories, including UV lights, fall into this category.

Portable heating and ventilation appliances, including space heaters and portable cooling units or dehumidifiers, also don't require permits. Evaporative or "swamp" coolers also don't need a permit for installation. Self-contained units with 10 pounds or less of refrigerant and are actuated by motors with

However, emergency replacements and repairs (per R105.2.1 in the IRC) also don't require a permit, at least not before performing the work. The only condition is that the permit application must be submitted to the AHJ within the next business day. This rule can come in handy when you can't wait for the permit submission process and need to do an emergency repair or changeout.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

What's Different About Pool Heaters w/ Bert Nov 30, 2023

Show notes

In this podcast, Bryan Orr and Bert discuss various aspects of pool heaters, focusing on issues that make them different from typical HVAC systems. They cover the basics of pool heaters - the main types (heat pumps and gas heaters) and how they operate similarly or differently from things HVAC techs work on regularly.

The bulk of the 45-minute podcast looks at common service and troubleshooting situations with pool heaters, which are usually installed by pool contractors initially and not HVAC contractors. Bryan and Bert talk through typical causes of common error codes and problems like units frequently going out on high pressure. They cover water flow issues and the role of pressure versus flow switches, the sizing and limitations of heat pumps, low ambient operation challenges, freeze protection, and proper refrigerant charging. There is also a good amount of discussion on gas pool heaters - frequent component failures due to heat and corrosion issues, piping considerations due to their large BTU capacity, and combustion troubleshooting basics.

Throughout the casual discussion, both hosts interject humor and personal stories related to their dealings with pool heater equipment, clients, and installations over the years. The overall message is that while heat pumps and gas pool heaters have some specialized considerations, much of the core knowledge needed to service them comes from foundational HVAC systems understanding combined with an awareness of the unique aspects covered in detail during this episode.

Topics Covered:

Types of pool heaters
How heat pump and gas pool heater operation compare to HVAC
Typical installation and service providers
Key components and design aspects
Common high-pressure issues and troubleshooting water flow problems
Low ambient operation challenges
Refrigerant charging considerations
Gas piping sizing for large BTU appliances
Corrosion issues and component failures
Combustion testing basics

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

Farads, Micro and Pico - Short #180 Nov 28, 2023

Show notes

In this short episode, Bryan explains the fundamentals of capacitance, focusing on the unit of measure: farads, including micro and pico.

Farads are named after scientist Michael Faraday and measure capacitance; one farad represents the capacitance of a capacitor in which one coulomb of charge causes a potential difference of one volt across the plates. Farads measure the storage of electrical energy and indicate the capacitor's ability to create a phase shift.

Since farads are large units, our capacitors are rated in microfarads (1/1,000,000 farads). Bigger capacitors have higher microfarad ratings and store more charge.

Capacitors create a phase shift and limit current on the start or auxiliary winding. (You'll read less current across the start winding than the run winding or common when a run capacitor is in the circuit.) The start winding helps get a single-phase motor up and running (but it isn't present on all motors). Three-phase power has three windings, and it has three sine waves 120 degrees out of phase with each other, all of which can apply directional force. A single-phase motor has two windings and only one sine wave, so it doesn't have that phase difference, making it difficult to start a motor. Capacitors charge and discharge at a different point of the sine wave, causing a phase shift.

A picofarad is 1/1,000,000,000,000 farad, which is smaller than the microfarads we use. However, our meters can auto-range into the picofarad scale if they read a very weak capacitor. You'll have to make sure your meter is reading in the microfarad scale, not the picofarad scale.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).

All About 90% Furnaces Nov 23, 2023

Show notes

Bryan Orr hosted a live podcast discussion all about 90% efficient furnaces with HVAC professionals Ty Branaman, Adam Mufich, and Matthew Bruner. They covered the basics of how 90% furnaces work compared to traditional 80% furnaces, troubleshooting tips, and best practices for installation and service.

A key difference with 90% furnaces is the addition of a secondary heat exchanger that extracts more heat from the exhaust gases before they go out the flue. This allows the furnace to achieve at least 90% efficiency. The condensing of water vapor in the exhaust also releases latent heat. However, the acidic condensate must be properly drained, and pipes must be corrosion-resistant. Proper airflow is also critical.

The experts emphasized starting any service job by carefully looking over the furnace and venting. Check for any signs of problems like leaks, debris buildup, or animals/pests blocking vents. Verify gas supply and use combustion analysis to optimize performance. When troubleshooting, methodically trace through the sequence of operations. Pressure switches, flame sensors, and airflow issues are common culprits.

The podcast concludes with a reminder that extensive training content on HVAC topics like this is available through HVAC School and other industry experts. Continuing education and an open, collaborative mindset are important for professional growth.

Key topics covered:

How 90% furnaces achieve higher efficiency with a secondary heat exchanger
Water condensation and corrosion concerns - importance of drainage and pipe material
Verifying gas supply, venting, airflow, and using combustion analysis
Troubleshooting tips - visually inspecting, tracing sequence of operations, checking pressure switches and flame sensor
Proper installation positioning and intake/exhaust vent sizing per manufacturer specifications

View the entire livestream with Ty on our YouTube channel HERE.

Learn more about the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.

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

Subscribe to our YouTube channel at https://www.youtube.com/@HVACS.

Check out our handy calculators HERE or on the HVAC School Mobile App (Google Play Store or App Store).