TJERNLUND V1, V1D, V2D CRAWL SPACE VENTILATORS 8500720, UnderAire V2D User Manual

UnderAire

™

Crawl Space Ventilators

Fan powered crawl space ventilation
quickly reduces moisture helping to
protect both home and occupants.

TTJJEERRNNLLUUNNDD

Model V2D

Two fans and large faceplate
sized for ventilation openings
through block foundations.
Includes thermostat, dehumidi­stat and pre-wired 6’ power
cord.

Model V1D

One fan and large faceplate sized
for ventilation openings through
block foundations. Includes
thermostat, dehumidistat and
pre-wired 6’ power cord.

Three models to choose from:

Model V1

One fan and small faceplate for
ventilation openings through brick
foundations. (Requires switch or
dehumidistat to activate. Multiple
ventilators may be controlled by a
single switch or dehumidistat).
Includes thermostat.

Suitable for Damp Locations

■ Ventilates excess moisture,

the cause of mold, mildew
and wood rot. Increases air
circulation to fight
condensation.

■ Constant operation helps vent

radon, treated wood off­gassing and odors that might
otherwise migrate into living
areas.

Facts to know

about Crawl Space

Ventilation

From Mississippi State University
Extension Service:

■ If soil is damp, as much as 20 gallons
of water per 24 hours can evaporate
into the air in a 1,400 sq. ft crawl
space.

■ Primary causes of excess moisture
include:

● Surface runoff water

● Poor ventilation

● No or poor ground vapor barrier

■ Signs of excess moisture in crawl

space:

● Soil is wet

● Surface organism growth on

floor joists

● Wet insulation

● Musty odors in crawl space or

living areas

● Excessive moisture in living areas

tending to migrate towards
windows

TJERNLUND PRODUCTS, INC.

1601 Ninth Street White Bear Lake, MN 55110-6794
Phone: [phone].255.4208 Fax: [phone]
Visit our web site: www.tjernlund.com

Copyright © 2006 Tjernlund Products, Inc. P/N 8500720

UnderAire

TM

Crawl Space Ventilators

Easy to install

Designed and engineered
for years of service

How to determine the number of

UnderAire™ Ventilators needed:

Galvanized face

plate may be

trimmed if

necessary

Thermostat
deactivates fan
below 40

0

F to

avoid freeze-ups

Ventilators are
installed inside crawl
space behind existing
ventilation opening.
Screws and masonry
wall anchors are
included.

Sealed bearing

motor(s)

Complete details on Tjernlund Crawl Space Ventilators are available from your Tjernlund distributor or at www.tjernlund.com

Models V1D and
V2D have 6'
grounded power
cord

Model V1 V1D V2D

Performance 110 CFM 110 CFM 220 CFM
Motor 115/1/60 115/1/60 2 @ 115/1/60

0.30 amps 0.30 amp 0.60 amps

Dehumidistat OFF/ON or OFF/ON or

20-80% RH 20-80% RH

Thermostat Opens at 40

0

F Opens at 400F Opens at 400F

Dimensions

14 3/8” x 6 7/8” x 2” 18” x 9” x 2” 18” x 9” x 2”

Specifications

Models V1D & V2D Model V1

Models V1D and V2D

include adjustable

dehumidistat

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. ÷ 15 minutes = 160 CFM of
ventilation. Choose two V1 or V1D ventilators or one V2D ventilator.

Other Tjernlund

ventilation products

In-Forcer™

fresh air and
combustion air
intake fans
automatically
bring outdoor
air into tightly
sealed homes.

Duct Booster

®

fans boost airflow
to hard-to-heat
or cool rooms.
Capacities from
150 to 1,200 CFM.

Optional Model DH10

dehumidistat available

separately