#charging

Tech Tips:

What Should My Subcooling Be?
This is the article you read BEFORE you call and ask a senior tech what your subcooling should be. It's also the one you send to a junior tech when they call and ask you: So, what is subcooling? (Or subcool, as many call it.) Subcooling is a measurement of the temperature DECREASE of a […]
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Which Hose Do I Use?
This tech tip is a companion piece to a recent short podcast episode about the same topic. It contains links to the specific products mentioned in that podcast. You can also learn more about NAVAC products as a whole at https://navacglobal.com/. Our trade has a lot of cool tools. But while we’re thinking about how […]
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Weighing Refrigerant In and Out
If you don't use a scale every time you add or remove refrigerant, I suggest you begin doing so immediately, if not sooner. Weighing in while charging is fairly obvious, and it's useful so you can keep track of what you are using and how much to charge a customer. When you have a system […]
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The “Approach” Method of Charging and Condenser Efficiency
We have discussed many methods for checking a refrigerant charge without connecting gauges over the last few years. Recently, I've been thinking about the “approach” method of charging that many Lennox systems require. What is the Approach Method? The “approach” simply refers to the temperature difference between the liquid line leaving the condenser and the […]
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Is it too cold to set the charge?
I've heard the phrase, “It's too cold to set the charge!” for as long as I've been in the trade. I've also heard some variations of, “We need to come back and set the charge,” or, “We need to come back to do XYZ [some other thing].” Granted, there are cases where you do actually […]
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Charging Systems with Accumulators
In air conditioning service, we don't always see systems with accumulators. In fact, they are pretty uncommon unless you work on a lot of heat pumps. However, as heat pumps gain popularity, charging systems with accumulators will be a good skill to have in your tool bag. We are Carrier dealers in Florida, so we […]
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Flash Gas
When we say that there is “flash gas” at a particular point in the system, it can either be a bad thing or a good thing, depending on where it is occurring. Flash gas is just another term for boiling. It is perfectly normal (and required) that refrigerant “flashes” or begins boiling directly after the […]
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Is It OK To Top Off With R410a?
I am consistently surprised by how much false information still circulates out in the field, and one of the ones I hear often is the idea that you cannot or should not “top-off” or recharge R410a systems on top of an existing charge of R410a when the system is low. So, to be clear, before […]
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What Should My Superheat Be?
  The most common—and often most frustrating—questions that trainers and senior techs get asked sound something like this: “What should my ______ be?” or “My _____ is at ______. Does that sound right?” Usually, when the conversation is over, both the senior and junior techs walk away feeling frustrated because the junior tech just wanted […]
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Videos:

Podcasts:

Residential & Rack Startup and Commissioning (Part 1)
 In this episode of the HVAC podcast, Bryan and Max Johnson from Kalos discuss the critical role of a startup and commissioning technician in the HVAC industry. Max, who has experience in both residential and commercial HVAC, shares his insights on the importance of understanding the scope of work, equipment specifications, and code requirements. […]
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Checking a Heat Pump in Heat Mode – Short #178
 In this short podcast, Bryan talks about checking the charge of a heat pump in heat mode. This skill will become more critical as ambient temperatures get cooler. The most reliable way to check and set the charge regardless of operating mode and season is to weigh the charge. This method is most practical […]
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Low Ambient, Condenser Flooding and Headmaster Valves Podcast Companion
Today, Jeremy Smith joins us to discuss low-ambient conditions and controls, condenser flooding, and headmaster valves. He has also given us a companion article on those subjects, which you can read below. Download the podcast directly HERE. As always, if you have an iPhone, subscribe HERE, and if you have an Android phone, subscribe HERE. […]
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