Installation Guide

DESCRIPTION
The Tjernlund UnderAire™ Series Crawl Space Ventilators are designed to circulate fresh outdoor air underneath homes
and porches. Excessive humidity levels in Crawl Spaces is the leading cause of premature rotting of support columns,
joists, floors and beam supports. Humidity can promote fungus growth and increased termite activity. Humidity may also
cause plumbing failures due to rust and corrosion. Constant operation helps vent radon gases, treated wood off-gassing
and other odors that might migrate into living areas. Deluxe models (V1D & V2D) are controlled by a dehumidistat which
actuates the fan if the relative humidity rises above the selected set-point.
IMPORTANT: All Ventilator models are equipped with a factory installed and pre-wired thermostat which will prevent opera-
tion of the fan below 35°F outdoor temperature. Normal operation of the fan will resume once the temperature outside rises
near 50° F.
SPECIFICATIONS
GENERAL INFORMATION
Each UnderAire™ Crawl Space Ventilator is electrically factory line tested before shipment.
After opening carton, inspect thoroughly for shipment damage. Fan should rotate freely and all electrical wires and connec-
tions should be secured. If any damage is found, notify freight carrier and your distributor immediately and file a concealed
damage claim.
RECOMMENDED VENTILATION RATE
Calculate the cubic area of the crawl space by multiplying the length x width x height. Divide this number by 15 to determine
the minimum CFM necessary to fully ventilate the space in 15 minutes. Example: 20’ wide x 40’ long x 3’ high crawl space =
2,400 cubic ft. 2400 cubic ft. divided by 15 minutes = 160 CFM of ventilation. Choose two V1 or V1D ventilators or one V2D
ventilator.
CRAWL SPACE VENTILATOR MODELS V1, V1D, V2D
©2013 TJERNLUND PRODUCTS, INC. ALL RIGHTS RESERVED P/N: 8504129 REV A
TJERNLUND PRODUCTS, INC.
1601 Ninth Street • White Bear Lake, MN 55110-6794
PHONE [phone] • [phone] • FAX [phone]
Visit our web site • www.tjernlund.com
READ OWNERS INSTRUCTIONS CAREFULLY PRIOR TO INSTALLATION.
THESE INSTRUCTIONS MUST REMAIN WITH EQUIPMENT. DO NOT DESTROY.
MODEL V1
MODEL V1D
MODEL V2D
MODEL V1 Ventilator:
Capacity: 110 CFM
Motor: 115 Volts ~ 50/60 Hz
0.30 amps maximum
Thermostat: On at 50°F
Off at 35°F
Dimensions: 14 3/8” x 6 7/8” x 2”
Mounting Plate Smallest
Trimmable Dimensions: 9 3/8” x 5 3/8”
MODEL V1D Ventilator:
Capacity: 110 CFM
Motor: 115 Volts ~ 50/60 Hz
0.30 amps maximum
Thermostat: On at 50°F
Off at 35°F
Dehumidistat: 20% - 80% RH Range
Dimensions: 18” x 9” x 2”
Mounting Plate Smallest
Trimmable Dimensions: 9 3/4” x 6”
MODEL V2D Ventilator:
Capacity: 220 CFM
Motors: 2 @ 115 Volts ~ 50/60 Hz
0.60 amps maximum
Thermostat: On at 50°F
Off at 35°F
Dehumidistat: 20% - 80% RH Range
Dimensions: 18” x 9” x 2”
Mounting Plate Smallest
Trimmable Dimensions: 14” x 6”