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What size in tons is a Panasonic air conditioner or heat pump from model number?
Friday, April 24, 2020
You can determine the “nominal” size of your HVAC system by examining the model number on the data plate at the side of the condenser (outdoor unit). Just like the nominal size of lumber or an air conditioning filter, the exact cooling capacity may be a little more or less than the nominal rating, but it’s close.
For Panasonic, you should look near the end of the model number. It will be a number divisible by 6 or 12, and represents the nominal BTU of the system in thousands. A ton of air conditioning equals 12,000 BTU, and 18 divided by 12 equals 1.5, so the data plate below indicates the system is 1-1/2 tons. The actual BTUs are also noted and, in this case they are slightly below the 18,000 nominal BTUs of of a 1-1/2 ton unit, which is typical.
Here’s a rundown of the range you will encounter: 12 = 1 ton, 18 = 1.5 tons, 24 = 2 tons, 30 - 2.5 tons, 36 = 3 tons, 42 = 3.5 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 is 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 a Panasonic system, go to our blog post How can I tell the age of a Panasonic heat pump or air conditioner from the serial number? To find out the age of another brand of air conditioner or heat pump, go to How do I determine the age of my air conditioner?
To learn more about heating and air conditioning systems, see these other blog posts:
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