Measure TESP in HVAC Two-Piece Air Handlers

What makes modular or two-piece different from their single-piece cousins when it comes to measuring total external static pressure (TESP)? In this article we’ll examine the differences and discuss how to measure TESP correctly. “As-Shipped” The “As-Shipped” idea is helpful when measuring the TESP of two-piece air handlers. So, what do you find when you …
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Testing HVAC Static Pressure

I hear a lot of reasons for taking static pressure measurements on every service call. One of the most common is that it takes too long — there isn’t enough time on a call to do it. Let’s face it, technicians have a lot of responsibilities and measuring static pressure adds to them. What if …
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Visual Clues to HVAC Comfort Defects

Many homeowners across the U.S. live in uncomfortable conditions. Sadly, most are convinced it’s normal. As an HVAC contractor, there are some common steps you can take to deal with their discomfort, and make conditions much more bearable. If you know what to look for, you can easily see the signs. Let’s look at the …
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Challenge is measuring static pressure on a variable speed fan

Measuring static pressure on air handling equipment that has variable-speed fans can be a challenge to both new and experienced technicians. By addressing a few details, your readings will be consistent when you encounter this blower type. Let’s look at three tips you can use the next time you measure static pressure on a variable-speed …
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Blood Pressure Monitor

When replacing HVAC equipment, better service companies offer duct upsize and system performance upgrades as an option to their customers. These upgrades allow the duct system to perform closer to the level of efficiency claimed by the equipment manufacturer. Let’s take a look at the steps necessary to effectively upsize a residential duct system. Why …
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Zero Draft and the CO Conundrum

Many technicians get distressed when they measure draft pressure in the flue and discover the reading is zero. Let’s look at three common reasons for zero draft pressure in a flue. We’ll also determine what defect you’re dealing with. Reason #1: Zero Draft from Building Depressurization Building depressurization is probably the most common reason for …
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Kinetic Energy is Energy in Motion

The use of energy is what drives an HVAC system. Many of us remember learning about potential and kinetic energy in high school and wondering, when will we ever use this stuff? The truth is potential and kinetic energy are both forces we either ignore or apply in our professional and personal lives. Let’s examine …
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Combustion Air in a Gas-Fired boiler

Safe operation of any fuel-fired equipment requires adequate combustion air supply. To provide this essential system component, technicians typically install openings constructed of metal ducts or fixed grilles. This provides air from the outside or from an adjoining part of a building. Since combustion air openings are ducts, let’s look at the variables affecting airflow …
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With the end of the heating season there’s a tendency to forget the dangers of carbon monoxide (CO). As you transition to the cooling season, be sure to keep your awareness for CO high even though it’s likely to be the last thing on your mind. Let’s look at five summer CO issues you should …
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HVAC Air Filter Media

If you’ve been in the HVAC industry for any length of time, you’re familiar with complaints involving dust and dirty equipment. As a result, most technicians target the air filter first when they receive such calls. As you investigate these problems, keep in mind how the following ways reduce filtration effectiveness so you can more …
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