#hvac

Recovery is the removal of refrigerant from a system. From there, you can either store it and send it in for recycling or reintroduce it back into the same system. Here are some top tips: Make sure your tank is empty and evacuated to 300 microns if you plan to return the refrigerant to the […]

This article was written by Don Gillis, the technical training manager at Chemours. Thanks, Don! Refrigerant compressors are essential components of air conditioning and refrigeration systems, as we all know. They work by compressing refrigerant vapor, which then flows through the system and changes state as pressure and temperature conditions rise and fall. Unfortunately, these […]

“It is only through the enforced standardization of methods, enforced adoption of the best implements and working conditions, and enforced cooperation that this faster work can be assured. And the duty of enforcing the adoption of standards and enforcing this cooperation rests with management alone.”  —Frederick Taylor “The objective of education is not to fit […]

“The very substance of our existing which has made us leaders in technique, stands as a barrier to any thinking which might be able to comprehend technique from beyond its own dynamism.” -George Grant The odd quote above takes some time to understand but has been rattling around in my brain for weeks now. George […]

The temperature of the refrigerant in the evaporator coil can really help us with diagnostics, but we need to know the targets we’re aiming for if we want to get the most out of it as a troubleshooting tool. If we take the return air temperature and subtract 35 degrees from that number, we get […]

This tech tip was submitted by Steve Rogers, the current president of The Energy Conservatory (TEC). Steve has been on the podcast several times in the past and is a valued contributor to HVAC School. Thanks, Steve! As summer approaches, HVAC technicians all over the US are preparing for those difficult conversations with occupants about […]

I recently read a tech tip by Matt Bruner about using the Manual D process. In the article, he designed a duct system for a small job using a ducted mini-split. One thing I noticed about his design was that the supply and return duct velocity was fairly low compared to the arbitrary 900-feet-per-minute supply […]

In my second year in HVAC, I went out with a senior technician to install a supply duct for a bathroom in a house. While he ran the duct, I cut a hole in the plenum and attached the collar. He crawled back across the attic and very nicely told me that people don’t typically […]

Enthalpy is easy. It's just a state function that depends only on the prevailing equilibrium state identified by the system's internal energy, pressure, and volume. It is an extensive quantity. Simple. Like most things, the scientific definition is as clear as mud. In HVAC/R, we use enthalpy measurement to come up with the total heat […]

I hear many techs complain about the finicky and ineffective nature of electronic leak detection. So much so that some claim that is is a waste of time altogether. we recently located a leak inside the fins of a ductless evaporator coil, pinpointed to an exact spot using an electronic leak detector. For demonstration purposes, we took […]

 Shelby Breger, co-founder of Conduit Tech, joins Bryan Orr on the HVAC School Podcast to discuss her company's innovative lidar-enabled design and sales software tool for HVAC contractors. Conduit Tech's software utilizes lidar sensors in iPads and iPhones to scan homes and create 3D models and 2D floor plans. It overlays load calculations factoring […]

 In this short podcast episode, Bryan dives into some belt talk, including some bits about pulleys and sheaves. He also shares some belt tensioning tips for your next commercial HVAC job. Belts are less common than they used to be, but we find them in ventilation fans, RTUs, and AHUs. Squealing belts indicate slippage, […]

 In this episode of the HVAC School Podcast, host Bryan Orr speaks with Chris Hughes of The Energy Conservatory (TEC) about using the Roomulator card and DG-8 manometer for room pressurization testing. Chris provides background on how he came up with the idea for the Roomulator. He wanted an easy way for technicians to […]

 In this short podcast, Bryan dives into a gas heating topic: primary & secondary air in combustion. Primary air is the air and oxygen content that enters the furnace BEFORE combustion. In older furnaces, prior to induced combustion, air was drawn in through the front. These older furnaces had adjustable shutters that we could […]

 In this solo podcast, Bryan provides an introduction to heat pumps, explaining the basics of how they work and key considerations in a way that is easy for anyone to understand. He starts by reviewing some core HVAC principles – that heat moves from higher temperatures to lower temperatures, the three main methods of […]

 This podcast brought together several women working in the HVAC industry to discuss their experiences and offer advice. The conversation focused on the positives of working in HVAC as a woman, the importance of community, and the resources available. The women talked extensively about how welcoming and supportive the HVAC community, and particularly HVAC […]

 This live podcast from AHR Expo 2024 discusses the costs of truck rolls for HVAC technicians and how technicians and companies can reduce those costs. Jim and Bryan highlight that every time a tech has to go to the supply house to get parts, the company loses money in potential service calls that could […]

 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 […]

 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 […]