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How do I find the size in tons of an Airdach air conditioner or heat pump?
Wednesday, October 12, 2022
The size in tons of an Airdach air conditioner or heat pump is determined with the first two numbers (after a series of letters) in the model number. They will be divideable by 6 or 12 and, since a ton of cooling equals 12,000 BTU, dividing that number by 12 will give the tonnage of the unit. So the one shown (ACTC3614NG1-D) below is 3 tons.
Here’s a rundown of the range you will likely encounter: 18 = 1.5 tons, 24 = 2 tons, 30 - 2.5 tons, 36 = 3 tons, 42 = 3.5 tons, 48 = 4 tons, and 60 = 5 tons.
If you are unsure whether you have found the right two numbers, you can double-check it by looking for the “RLA” rating on the data plate. RLA is an acronym for Rated Load Amperage, and is what the maximum amperage should be when the condenser up and running. If you divide the RLA by 6 for older units and 5 or 6 for newer units, you should get a number that approximates (not exactly) the tonnage of the system. Make sure you use RLA and not LRA, Locked Rotor Amperage, which is the surge of amps necessary to overcome inertia and start the system. It averages around five times the RLA.
To determine the age of an Airdach system, go to our blog post How to I find the age of an Airdach air conditioner or heat pump? For the age of another brand or manufacturer, go to our blog post How do I determine the age of my air conditioner?
And to figure out what all the other numbers listed on the condenser data plate mean, go to our blog post How do I understand the air conditioner or heat pump condenser label (data plate)?
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To learn more about heating and air conditioning systems, see these other blog posts:
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