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HVAC Temperature Measurement Conversion - In air conditioning and heating applications it is necessary to accurately measure temperature to offer control of the temperatures relative to the application for which the HVACR equipment is serving. There are four separate temperature scales used to measure temperature and it becomes necessary at times to have the ability to convert between the different scales.
Aside from the temperature measurement scales and their use in HVAC, there are also methods for using specific tools to make those measurements. For example, in many cases, a technician needs to know the dry-bulb temperature and the wet-bulb temperature. In the old days, a technician would use a sling psychrometer to get the wet-bulb temperature.
Today, there are digital instruments that will measure the wet-bulb temperature for the technician. Here we begin with temperature conversion:
HVAC Temperature Measurement Conversion
The two most common scales used by most people are Fahrenheit and Celsius. Fahrenheit is mostly used in the United States where the culture has resisted changing from standard measurements to the metric system. Celsius is used throughout the world including the United States and Canada. Scientist often uses Kelvin and Rankine measuring scales to measure temperature.
These temperature scales, Rankine and Kelvin, are uncommonly used in popular culture no matter where you live in the world except by the scientific community and are often used to measure extreme temperatures.
Temperature Conversion
Degrees Celsius to Degrees Fahrenheit
1.8 X Temperature Celsius + 32 = Temperature Fahrenheit
Degrees Celsius to Kelvin
Degrees Celsius + 273 = Kelvin
Degrees Fahrenheit to Degrees Celsius
(Temperature Fahrenheit - 32) / 1.8 = Temperature Celsius
Degrees Fahrenheit to Degrees Rankine
Temperature Fahrenheit + 460 = Degrees Rankine
Kelvin to Degrees Rankine
1.8 X Kelvin = Temperature Rankine
Kelvin to Degrees Celsius
Kelvin - 273 = Degrees Celsius
Admittedly, it is unusual for a technician to have to convert in the field except in some cases where the manufacturer of any given product did not enclose the proper paperwork with their new equipment, or perhaps a mistake was made and the proper paperwork was not included with the new equipment.
I think the only way a technician would require these conversions on a regular basis is if they worked in a lab of some kind and they were constantly crunching data. It doesn’t matter, it is still good to have a reference for these things when they do occur. Be proficient to stay ahead of the pack.
The Field and Practical Application | HVAC Temperature Measurement Conversion
From experience, the only time I’ve ever needed to make conversions in the field was with products that were manufactured in another country. A few times the installation instructions were not in English which made things a little difficult. I know it may seem to be odd for someone to actually admit they read instructions but with technical things it is a good habit to follow.
You have to figure out the purpose of things and how and why they were engineered. It’s kind of like buying some of those “put it together yourself” furniture products except this is HVAC stuff so it does require some basic knowledge to figure out the how and why. And then there are some things that you absolutely know the “how and why” but you want to run it by someone else to support that hypothesis.
Either way, whenever you make the phone call or ask someone for their opinion, you want to have all the information to give them your take on the matter. That includes any temperature conversions you may want to throw in there with your description of the “how and why”.
HVAC Temperature Measurement Conversion
Technical Resource: Refrigeration and Air Conditioning Technology
