Therma-Stor Ultra-Aire 65H Manual Download Page 6

Page: 6 / 16

4.4B Ducting for Fresh Air — Option

Fresh air may be brought into the structure by connecting an
insulated duct from outside the structure to the 6" inlet of the
Ultra-Aire 65H. Advantages of this form of ventilation include:

1. Outside air is filtered before entering the building.
2. Outside air will be dehumidified before entering if the

Ultra-Aire 65H is running in dehumidification mode.

3. Drawing air from outside and blowing inside aids in

slightly pressurizing the structure. This helps prevent
dirty and humid air from entering elsewhere. It also
reduces the potential for carcinogenic radon gas to
enter and provides a small amount of make-up air for
open combustion and exhaust devices like the clothes
drier, fireplace, and water heater.

4. Exhaust fans are recommended in the bath rooms and

kitchen.

In cold climates or areas where the outdoor dew point is low
at times, ventilation can be used to dehumidify the structure,
making the Ultra-Aire 65H capable of year-round drying. This
is accomplished by bringing the dry, low dew point air into
the structure during these times. This approach is often more
economical than running the dehumidifier to remove excess
moisture from the structure. In cold climates, adequately
ventilating is critical to reduce the inside moisture content
and avoid moisture accumulating in the wall cavities. TIP: if
your house experiences condensation on the interior surface
of the windows during the winter, increasing the amount of
ventilation will often solve the problem.

An insulated 6" diameter duct is generally sufficient to
provide up to 65 CFM of outside air. Large quantities of
outside air will impact Ultra-Aire 65H performance positively
or negatively, depending upon the inside and outside air
conditions. The outside air duct should be connected to the
front of the unit. With a standard tee, the amount of outside
air can be restricted with a blade damper.

4.4C Installation in a Basement or Crawlspace with an

Existing Forced Air HVAC System.

Basement Installation:

Install a separate 8" return for the

Ultra-Aire 65H in a central area of the structure. Optional:
Duct the supply of the Ultra-Aire to a 8" x 8" x 8" tee/damper,
adjusted to 20% open to the basement. Duct the other side
of the tee to the air supply of the existing HVAC system with a
backdraft damper.

Crawlspace Installation:

Install a separate return for the

Ultra-Aire 65H in a central area of the structure. Optional:
Duct the supply of the Ultra-Aire 65H to a 8" x 8" x 8" tee/
damper that is 20% open to the crawlspace if desired. Duct
the other side of the tee to the air supply of the existing HVAC
system with a backdraft damper.

Instead of installing a separate return to the Ultra-Aire 65H,
and if the existing system has multiple returns, it is possible
to select one to disconnect from the existing forced air
system and use it for the dedicated Ultra-Aire return. Always
select a return from a central location in the structure in an
area that is always open to the rest of the structure. Do not
use a return from a room that may have its door closed much
of the time or, alternatively, install a separate return from the
open part of the house.

4.4D Installation in an Attic with an Existing Forced Air

HVAC System

CAUTION

ALWAYS place a drain pan under the unit if it is

suspended above a finished area or above an area where

water leakage could cause damage.

The interrupt switch should be installed in series with the field
wire that connects the blue (#5) lead from the Ultra-Aire 65H to
the blue (#5) lead on the control panel. If overflow occurs, this
switch opens the compressor control circuit and stops water
production before the drain pan overflows. The Ultra-Aire 65H
will continue to ventilate or circulate air as normal, but will not
dehumidify until this switch closes.

FOR HVAC INSTALLER ONLY

Ultra-Aire 65H Installer’s & Owner’s Manual

Ultra-Aire
Indoor Air

Return

DEH 3000

control

Heating/AC Return Air

Backdraft
Damper

Dry Air to
Basement

Gravity
Damper

Motorized
Damper

Optional
Fresh Air
Intake