#HVAC design

Tech Tips:

Equipment Changes, Ducts are Forever
By:Matthew BrunerI’m installing the HVAC system for a house that is being completely gutted. It has vaulted ceilings throughout, and a small attic area was designated for mechanicals. The duct system can’t go in the attic because there basically isn’t one. The engineer intended the equipment to go in the attic mechanical space, and then […]
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Manual J Field Data: Ducts
By:Matthew BrunerUnderstanding the relationships between ductwork, home comfort, and the load on a house is a complicated and dynamic problem. There are a large number of variables. Some of the data is fairly straightforward, like the other elements of field data collection we have covered so far in this series. Ductwork has different levels of […]
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The Ups and Downs of High-Performance HVAC
This tech tip recaps the livestream by the same name, featuring HVAC School contributors Matt Bruner and Adam Mufich and special guests Michael Housh, Chris Hughes, and Dustin Cole. You can watch that livestream on our YouTube channel HERE. “High-performance HVAC” is a term we hear quite a bit these days, but it’s not easy […]
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Manual J Field Data: Windows
By:Matthew BrunerA manual J load calculation will require you to input the U-value for the windows or “fenestrations” on the house. Fenestration is a fancy construction word for window. Figuring out the U-value and SHGC of a window on an existing home is very difficult. But first, let’s dive into what the terms U-value and […]
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Solving Comfort and IAQ Issues in a Vintage Home: A Case Study
By:Bryan OrrThis tech tip is a recap of the Santa Fe Dehumidifiers and Comfort Dynamics, Inc. case study about a 1941 vintage home in Miami, FL. You can listen to the podcast about that case study by clicking the play button below, and you can read the case study at https://hvacrschool.com/case-study. Special thanks to Nikki […]
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Manual J Field Data: Walls
By:Matthew BrunerThis article will cover how to collect field data for walls on an existing home for an ACCA Manual J calculation. In full disclosure, I had never collected any field data for a Manual J before I wrote this article. Many of the methods discussed were suggested by HVAC technicians and contractors in an […]
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The Wide-Narrow-Wide of Manual J
By:Matthew Bruner Starting to work on a Manual J load calculation can feel extremely overwhelming. How do we know what to focus on? What does normal look like? What if I’m way off on something and install way too big or small of a unit? On a practical level, what is the payback or value […]
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Sensible Heat Ratio (SHR)
By:Bryan Orr Every piece of air conditioning equipment can move a certain amount of heat BTUs (British Thermal Units) at set conditions. In most cases, during the cooling mode, a portion of those BTUs will go toward changing the temperature of the air, and a part will go toward changing vapor water in the air […]
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But My Old Unit Worked Fine?!
By:Genry GarciaHow an A/C System got to be Oversized (Maybe) But My Old Unit Worked Fine?! Most of us have heard this at some point. This complaint typically comes from a particularly unhappy customer after the installation of a brand new A/C system. Throughout this article, we’re going to explore the possible root causes of […]
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Catching Up at the Amply Booth
By:Bert TestermanEric FitzEd Smith
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Manual J in 15 Minutes?
By:Bryan OrrShelby Breger  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 […]
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Getting Your Foot in B.S. – A Beginner’s Guide to Getting Into Building Science
By:Alex Meaney NOTE: If you cannot view the recording, the video may still be processing. The maximum wait time is 24 hours. We apologize for the delay and appreciate your patience.
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