Figure 26.
Extreme transition in duct work
Installation
OAU-SVX01K-EN
29
•
Discharge Air sensor should be placed in the center of
the ductwork at least 4 feet from the unit or after the
first 90° bend.
General Unit Requirements
The checklist listed below is a summary of the steps
required to successfully install a commercial unit. This
checklist is intended to acquaint the installing personnel
with what is required in the installation process. It does
not replace the detailed instructions called out in the
applicable sections of this manual.
Check the unit for shipping damage and material
shortage. File a freight claim and notify appropriate
sales representative if damage or shortage is
discovered.
Verify that the unit nameplate model, options, and
voltage are correct.
Verify that the installation location of the unit will
provide the required clearance for proper operation.
Assemble and install the roof curb (if applicable).
Refer to the latest edition of the curb installers guide
that ships with each curb kit. Check curb for level
installation; if not level, shim as required.
Set the unit onto the curb; check for level.
Ensure unit-to-curb seal is tight and without buckles
or cracks.
Install and connect proper condensate drain line to
the evaporator condensate pan drain connection (see
).
Main Electrical Power Requirements
Verify that the power supply complies with the unit
nameplate specifications.
Inspect all control panel components; tighten any
loose connections.
Connect properly sized and protected power supply
wiring to a field-supplied/-installed disconnect switch
and to the main power terminal block (HTB1) in the
unit control panel.
Connect properly-sized earth ground.
Note: All field-installed wiring must comply with NEC
and applicable local codes.
Condensate Drain Configuration
OAU units are selected based on dehumidification
capability. As such, condensate can form at a high rate.
Therefore, the OAU drain pan and condensate line are
sized and designed accordingly. However, an often-
overlooked element of proper condensate drainage is
proper P-Trap and drain line sizing and installation. An
incorrectly-designed and -installed P-Trap can restrict
condensate flow or cause water in the condensate drain
pan to “spit” or “geyser” which may cause condensate
overflow. Carefully install and trap the drain pan to ensure
adequate condensate removal under all conditions.
An evaporator condensate drain connection is provided
on each unit.,
, and
appropriate
A condensate trap must be installed at the unit due to the
drain connection being on the “negative pressure” side of
the fan. Install the P-Trap using the guidelines in
.
Pitch drain lines connected to P-Trap at least 1/2 inch for
every 10 feet of horizontal run to assure proper
condensate flow. Do not allow the horizontal run to sag
causing a possible double-trap condition which could
result in condensate backup due to “air lock”.
RETURN DUCT
SUPPLY DUCT
EXTREME TRANSITION IN DUCTWORK
CAN CAUSE RESTRICTION.
DISCHARGE AIR SENSOR
LOCATION
