The concealed air handler would be located lets say in the master bedroom in the attic space above the exterior window. The return duct would be twice the size of the intake of the air handler but the length of the return would be lets say 32 feet long.
The idea is that the conditioned air would travel from the source across the bedroom through the bathroom and finely arrive at the return in the walk in closet.
It seem to me the units CMF spec's should not be affected by extremely long return if it is sized properly?
Spec for a Mitsubishi SEK-KD09NA4 air handler| Power Supply
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Phase, Cycle, Voltage
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1 Phase, 60Hz, 208/230V
*4
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Cooling
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Rated Capacity
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8100 Btu/h (2.37 kW)
*1
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Capacity Range
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3800 - 10900 BTU/h (1.1 - 3.2 kW)
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Total Input
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670 W (0.700 kW)
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Energy Efficiency SEER
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15
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Sensible Heat Factor
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0.8
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Heating at 47° F
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Rated Capacity
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10900 Btu/h (3.2 kW)
*2
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Capacity Range
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4800 - 14100 Btu/h (1.4 - 4.1 kW)
|
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Total Input
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1020 W
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HSPF (Region IV)
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10
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Heating at 17° F
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Maximum Capacity
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6700 Btu/h (2 kW)
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COP
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2.42 Btu/Btu
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Minimum Circuit Ampacity
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MCA
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1 Ampere
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Recommended Fuse/Breaker Size
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15 Ampere
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Refrigerant
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Type
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R410A
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External Static Pressure
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0.02 -0.06-0.14 -0.20 In. WG (5 -15-35 -50 Pa)
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Airflow
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Cooling : DRY
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194-247-317 CFM (5-7-9 m³/min)
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Cooling : WET
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174-222-285 CFM (5-6-8 m³/min)
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Heating : WET
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174-222-285 CFM (5-6-8 m³/min)
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Sound Pressure Level
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23-26-30 dB(A)
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Dimensions H x W x D
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Height
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7-7/8 Inches (200 mm)
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Width
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39 Inches (990 mm)
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Depth
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27-9/16 Inches (700 mm)
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