Over size Blower / Less Dehumidication

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Poncho

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Replaced my old Lennox Pulse Furn and Trane AC w/Amana units. Now I think theres too much wind going thru Evap 'cause now have LESS Condensate. Also, the supply ducts sound 'bout like a Wind Tunnel....WTF.
Spent 9 Large now got Noise. Is it me....or is the Amana Hi Eff units justa thata way ???
 

Stuff

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Nothing to do with the brand. Ask the installers if they can lower the blower speed. If not it means the system is too big for your ductwork.
 

Dana

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Higher SEER often results in worse latent load performance, independently of whether the equipment is right-sized for your ducts (or cooling load.) Being oversized for the sensible load hurts as well.

Unfortunately oversizing by 2x or more is rampant in the industry. Hiring a competent third party such as an engineer or RESNET rater to run an aggressive Manual-J costs $500-800 in my area, but you're more likely to end up with right-sized equipment that way.
 

WorthFlorida

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Alot may have to depend on when you home or ductwork was installed. When SEER 10 was about the best you can do ductwork installed was not really a big factor on cooling for residential homes. As AC units got better and the SEERs went up, one trick was to blow a larger volume of air slower over the coils so the outlet of the air handlers were increased. Also ductwork was sized up. If at one time an 8" duct was the norm, now it would be a 10" or larger. Smaller ductwork usually will result in higher air flow.

Just about all blowers motors are multi-speed. It is either by changing a switch option or just connecting the power to a different connector on the motor. If you have the manual it may have a set of instructions to change the fan speed. When you get to the very high efficient AC units (SEER 18 or higher) the blower motor will run at different speeds (variable) depending on outdoor/indoor air temp, humidity levels and the set point of the thermostat.

Since you have a furnace/blower set up, usually in heat mode the fan blows slower and when it is switched to cooling the fan speed is increased. This is also true with an AC air handler with an electric heating element for residential heating. Just to give it a try move your thermostat to heat and turn it on and listen if the noise is reduced or at the thermostat turn on the "fan". This will usually run the fan at the slower heating speed. The company or tech that installed your system can easily change it for you. It is really all part of the install.
 

Poncho

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First, a big hoooaaahhh and thank you for your service. Also, thanks for tak'n the time for the informative git back. Gonna sic my installer on this detail.
 

Poncho

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Higher SEER often results in worse latent load performance, independently of whether the equipment is right-sized for your ducts (or cooling load.) Being oversized for the sensible load hurts as well.

Unfortunately oversizing by 2x or more is rampant in the industry. Hiring a competent third party such as an engineer or RESNET rater to run an aggressive Manual-J costs $500-800 in my area, but you're more likely to end up with right-sized equipment that way.
Thank you Sir for the info.
Higher SEER often results in worse latent load performance, independently of whether the equipment is right-sized for your ducts (or cooling load.) Being oversized for the sensible load hurts as well.

Unfortunately oversizing by 2x or more is rampant in the industry. Hiring a competent third party such as an engineer or RESNET rater to run an aggressive Manual-J costs $500-800 in my area, but you're more likely to end up with right-sized equipment that way.
Dana, thanks for the Reply an tak'n the time to reach out.
 

Poncho

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Nothing to do with the brand. Ask the installers if they can lower the blower speed. If not it means the system is too big for your ductwork.
Thanky Sir, appreciate the gitback...
 

Jadnashua

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I'm a big advocate of variable speed fan motors (mine is 16-speed). It starts out slow, running the air over the coils slowly, pulling lots more moisture, and only ramps up if the set point wasn't met. Then, it ramps down slowly after the compressor shuts off to extract as much cooling from the coils as possible.
 

Dana

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A post-cycle ramp down of an air handler re-injects some of water that had condensed onto the coils back into the house, yielding lousier latent load management than just turning it off. Right sizing for the 1% design load and a fully variable COMPRESSOR as well as air handler can do it better while still yielding a high as-used SEER.
 
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