A little help in deciphering model numbers and understanding what a decibel really means may help when looking for sound ratings in the various models of heat pumps . It’s critical to measure like units. For example, a 14 SEER Trane with a 14 Seer Carrier.
- Under each chart is a link to my source of information
Table Of Contents
- What’s A Decibel (dBA)
- What Do I Have To Compare Heat Pump Sound Ratings To?
- Goodman 14 SEER Sound Ratings
- Trane 14 SEER A-weighted Sound Power Level [dB(A)]
- Lennox 14 SEER Sound Rating Number
- Carrier A-Weighted Sound Power (dBA) With Sound Shield
- York LX Series Octave Band Sound Power Level
What’s Are Decibel Sound Ratings?
So here’s an attempt to describe decibels. Decibels are arranged in a logarithmic scale. 85 dB is 1500% louder than 70 dB. Going up one decibel in sound is not just slightly louder, it’s a lot louder.
We are more familiar with and can relate more to linear scales where the value between a couple points is always equal. In a logarithmic scale the value between points of the scale change according to a pattern.
If a sound that is 70 decibels is increase to 80 decibels, it means that it’s intensity is 10 time stronger.
On the chart below I looked at dishwasher, there’s no way my dishwasher is louder than my vacuum cleaner. I have to agree with the washing machine, we have to shut the door on the thing or you have to raise your voice to hear one another.
What Do I Have To Compare Heat Pump Sound Ratings To?
This is all very ambiguous. Let me just start off by saying that a recent heat pump (Goodman) that I started up with me and the customer standing right next to it, his comment was “that’s really quiet” and we didn’t have to raise our voices a single octave to hear each other.
Another big consideration in noise level is that some sounds for you may not be good for me and vice versa. It’s somewhat like reading the temperature. I had 7 identical thermometers and they read 7 different temperatures. So I guess we pick the one we like and be satisfied. No?
You should read my article on which heat pump is the quietest. I think you’ll have some new ways of thinking about what unit to buy.
What I am trying to impress upon you if you are thinking about buying a new heat pump or air conditioner is, are these manufacturers measuring decibels with the same meter, from the same distance, in the same atmosphere?
A warehouse echos verses a room prepared to measure only the unit.
Air filters have come up with a common test called the MERV rating. It put all manufacturers of filters on the same test footing. There are a couple that still use there own test.
Back to Table of Contents
Goodman 14 SEER Sound Ratings
With Goodman the GSZ is the series of the model. The next two numbers represent the SEER rating, in this case it’s 14 SEER.
The next three numbers will tell you the tons. Since there is 12,000 BTU’s in a ton of refrigeration, then a model number with a 018 would be 18 divided by 12 which would equal 1.5 tons. The 024 would be 24 divided by 12, and now you’re looking at a 2 ton unit.
I know it’s funny math, but every industry has some quirks. You just kind of forget zeros when trying to decipher tons out of HVAC equipment model numbers.
The rest of the model number has to do with revisions. Not too important for these data charts.
| Model # | Tons | Decibels |
| GSZ140181L | 1.5 | 74 |
| GSZ140241K | 2 | 72 |
| GSZ140301K | 2.5 | 74 |
| GSZ140361K | 3 | 74 |
| GSZ140421K | 3.5 | 75 |
| GSZ140481K | 4 | 75 |
| GSZ140491K | 5 | 76 |
Trane 14 SEER A-weighted Sound Power Level [dB(A)]
A-weighted decibels, abbreviated dBA, or dBa, or dB(a), are an expression of the relative loudness of sounds in air as perceived by the human ear. In the A-weighted system, the decibel values of sounds at low frequencies are reduced, compared with unweighted decibels, in which no correction is made for audio frequency. This correction is made because the human ear is less sensitive at low audio frequencies, especially below 1000 Hz, than at high audio frequencies.
TechTarget Whatis.com
A note that Trane has included under there ratings says it’s tested in accordance with ARI Standard 270.95 but it not listed with ARI?
If you are a scientist in the field of sound you may still have an issue finding the quietest heat pump. I struggle to understand why a 5 ton 14 SEER Trane would be 4 decibels quieter than a 4 ton unit? It’s true in other brands, not just Trane.
According to our logarithmic scale 76 dBA 4 ton unit is a lot more noise than 72 dBA of the 5 ton.
| Model # | Tons | Decibels |
| 4TWR4018D | 1.5 | 76 |
| 4TWR4024E | 2 | 71 |
| 4TWR4030D | 2.5 | 76 |
| 4TWR4036D | 3 | 76 |
| 4TWR4042D | 3.5 | 76 |
| 4TWR4048D | 4 | 76 |
| 4TWR4060E | 5 | 72 |
Lennox 14 SEER Sound Rating Number
Lennox states their testing is done with test conditions included in AHRI Standard 270. So we’re getting some apples vs apples here, hopefully
| Model # | Tons | Decibels |
| 14HPX-018 | 1.5 | 76 |
| 14HPX-024 | 2 | 76 |
| 14HPX-030 | 2.5 | 76 |
| 14HPX-036 | 3 | 79 |
| 14HPX-042 | 3.5 | 79 |
| 14HPX-048 | 4 | 80 |
| 14HPX-060 | 5 | 80 |
Carrier A-Weighted Sound Power (dBA) With Sound Shield
The sound shield is a compressor blanket.
| Model # | Tons | Decibels |
| 25HCE-018 | 1.5 | 68 |
| 25HCE-024 | 2 | 74 |
| 25HCE-030 | 2.5 | 77 |
| 25HCE-037 | 3 | 76 |
| 25HCE-042 | 3.5 | 74 |
| 25HCE-048 | 4 | 79 |
| 25HCE-060 | 5 | 73 |
York LX Series Octave Band Sound Power Level
Not gonna make a chart for York. It’s complicated. But you can go here and when you arrive at the pdf file just hold down your Ctrl key and touch your F key. You will get a search bar at the top right of your screen. Copy and paste this next line into the search bar.
Octave Band Sound Power Level
Or you can scroll through the pdf file and find it.
There’s your York information.
Conclusion
I’d talk with some friends or relatives and go listen the there outdoor units and get some opinions. Do some listening and observe the locations of the different installations.
Take a quick look at this article that I wrote about 30 questions you should ask or know to ask before purchasing a new HVAC system.
I cringe when my neighbors noisy air conditioner comes on. That twang from the compressor when it starts during those peaceful summer nights when my bedroom window is open.
It’s a 20 year old Coleman. The new stuff made today would be so much quieter. Maybe someday I’ll get to upgrade that for him.
