Install Instructions

ManualsBrandsAprilaire ManualsDehumidifiersModel Dehumidifier (80 Pint Per Day)

DETERMINE VENTILATION REQUIREMENTS

CALCULATING AIRFLOW REQUIREMENT

1. The MINIMUM ventilation requirement is calculated using ASHRAE

62�2-2010�

ASHRAE Airflow in CFM = [House Area in Sq� Ft� x 0�01] +

[(Number of Bedrooms +1) x 7�5]

NOTE: Use ‘Number of Bedrooms + 1’ or ‘Number of Occupants’,

whichever is larger�

2. TABLE 1 shows the calculated airflow values to the nearest 5 CFM�

3. Record the required CFM� ________

TABLE 1 – CFM REQUIRED

House Sq. Ft.

Number of Bedrooms

2 3 4 5 6

1000 35 40 50

1500 40 45 55 60 70

2000 45 50 60 65 75

2500 50 55 65 70 80

3000 55 60 70 75 85

3500 75 80 90

DETERMINE FRESH AIR DELIVERY RATE

1. Measure the negative static pressure of the return system at the location where the fresh air intake duct enters the return duct or dehumidifier

inlet�

2. See TABLE 2 for estimated inlet airflow in CFM, based on duct type, length and available negative pressure� Use an airflow measuring device for a

more accurate airflow delivery rate�

3. Record the delivered CFM� ________

TABLE 2 – CFM DELIVERED

Duct Length

Negative Static Pressure ("w.c.) as Measured for Return Duct or Plenum

0.05 0.1 0.15 0.2 0.25 0.3

Flex Pipe Flex Pipe Flex Pipe Flex Pipe Flex Pipe Flex Pipe

10 ft. 60 65 85 90 105 110 120 125 135 140 150 160

20 ft. 55 60 80 85 100 105 115 120 130 135 140 150

30 ft. 50 55 75 80 95 100 110 115 125 130 130 140

NOTE: For the table above, 6" flex duct is laid loose with two, wide 90° bends and a fully opened damper� Rigid pipe values are based on 6" duct, two

90° elbows, and a fully open damper� In both cases, the air intake is through a metal vent hood with inlet screen� Airflow may need to be adjusted up

or down for variations in duct work�

DETERMINE CYCLE TIME

1. Use the Required CFM and Delivered CFM from the above steps to determine the Cycle Time from TABLE 3�

2. The values highlighted in gray cannot be set due to the maximum 60 minute Cycle Time� A second ventilation device (i�e�, bigger duct or second

duct) will be required to meet ventilation needs�

TABLE 3 – CYCLE TIME SETTING (MINUTES) FOR AIRFLOW DELIVERED VS. AIRFLOW REQUIRED FOR 1 HOUR CYCLE

CFM Delivered

CFM Required

20 30 40 50 60 70 80 90 100

60 20 30 40 50 60 70 80 90 100

80 15 25 30 40 45 55 60 70 75

100 15 20 25 30 35 40 50 55 60

120 10 15 20 25 30 35 40 45 50

140 10 15 15 20 25 30 35 40 45

160 10 10 15 20 25 25 30 35 40