What is a Thermocouple?
In HVAC, we work with thermocouples for temperature measurement all the time, but we may not understand the difference between a thermocouple and other types of temperature measurement sensors. A thermocouple is just two different types of metal connected at a “junction” that generates a small voltage with a temperature change. Older furnaces would often […]
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Some Furnace Questions
I received an email from a podcast listener with some furnace-related questions. Based on the nature of the questions, I figured it would be better to ask an experienced furnace tech. Benoît Mongeau agreed to help by answering the questions.  My name is Matt and I am a newer tech (fully licensed this September, have […]
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An Electric Heat Mistake
I started working as a tech when I was 17 years old, fresh out of trade school. My first winter out on my own, I went to a service call in an older part of Orlando, a part of town I had never worked in before. It was an especially cold winter that year, and […]
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Clocking a Gas Meter (It’s not that hard)
I've heard a lot made of clocking gas meters over the years, and honestly, in Florida, there isn't too much call for heat. There are even fewer furnaces. I was pleasantly surprised when I found out how easy it actually is. Here is how you do it, step by step: #1 – Make sure all […]
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Testing a Thermocouple
First, a thermocouple is not a flame rectifier like a modern flame sensor. A thermocouple actually generates a millivolt potential difference when it is heated by a flame—just to get that out of the way for any of you newer techs who are used to modern flame sensors. With higher efficiency gas-fired equipment being the […]
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Condensate Drainage in a High Efficiency Gas Furnace
This article was written by HVAC/furnace technician Benoît Mongeau. Thank you, Ben.     High efficiency (or 90%, or condensing) furnaces use a set of two heat exchangers to retrieve more heat from the combustion products than their mid-efficiency counterparts. Because of this, they generate flue gases much colder than those of a mid-efficiency or […]
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A Steam Heating Primer
With cold temperatures right around the corner, it is a good time to brush up on our steam now, and there's no better way to do that than by reading an article by Dan Holohan. This article was written by Dan Holohan and published at HeatingHelp.com HERE. It has been reposted here with permission. This […]
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TH, TR, and TH/TR Gas Valve Terminals
Jesse Grandbois is one of the techs who reads the tech tips, and he wrote a few tips that he wanted to share on some gas furnace control basics. This tip is about the basic terminal designations on a typical 24v gas valve. Thanks, Jesse! Have you ever noticed the TH/TR terminal on a gas […]
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Simple Pump Selection Part 2
Another follow-up article by Michael Housh… Enjoy! In this article, I thought I would show a pump curve and match it up with our system head-loss curve that we created in the last article, but before I do that, I thought I would talk a little bit more about the system head-loss curve and why […]
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