(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
Air Technology Systems, Inc.
1.6 General Design
The
CeilAiR
unit is housed in an aluminum frame type cabinet and is rated for indoor use. Access panels are lo-
cated on the front and rear of the cabinet for easy access to all components. Additional access may be obtained
to some components through the bottom of the unit on spot cooler confi gurations. The unit has an electrical box
inside the cabinet with a removable panel for accessing the electrical components. Operator controls may be
conveniently located on a wall within the space to be conditioned.
NOTE
Customer specifi ed non standard features or design variations may not be described in this manual. Refer
to the installation and electrical drawings supplied with your unit for details on additional feature(s). In some
cases, an addendum to this manual may also be included to further describe the feature(s).
1-6
1.6.1 Electric Box Access
The electrical components are protected in an enclo-
sure located in the cabinet behind an access panel.
Before opening the access panel, turn off power
at the main power service disconnect switch. This
removes power from the system controller and shuts
the unit off.
1.6.2 Coil(s)
The cooling and optional hot water reheating coils
are aluminum fi nned/copper tube construction. The
coils are leak tested and cleaned before installation
by the factory.
1.6.3 Blower
The unit is equipped with a centrifugal blower with
forward curved blades. The blower is contained in
a double-width, double-inlet housing. The blower is
dynamically and statically balanced to minimize vi-
bration. The blower motor is ODP industrial duty and
utilizes permanently lubricated ball bearings.
Smaller
CeilAiR
units (models OHS-012/040) use
direct drive blowers (except “H”-series models confi g-
ured for horizontal discharge).
Larger units (models OHS-048/120) and horizontal
discharge units (models OHS-012/040-H), use a
belt driven blower. The belt driven blower motor is
mounted on an adjustable base for belt tensioning
and is furnished with an adjustable pitch sheave to
adjust blower speed (see Figure 13).
1.6.3.1 EC Blower
As an option,
CeilAiR
OHS units
utilizing the
E²
controller
may be provided with high effi ciency
Electronically Commutated (EC) blower(s). The EC
blowers are equipped with backwards curved impel-
lers designed for high aerodynamic effi ciency, which
results in lower power consumption, lower noise
levels and longer operating life. EC blowers utilize
a brushless motor equipped with permanent mag-
nets and permanently lubricated ball bearing. The
fan speed is variable via a 0-10VDC signal from the
system controller..
1.6.4 Temperature Sensor
As a standard for systems utilizing a wall mounted
A-Tech 1.1 or A-Tech 1.2 thermostat, the temperature
sensor is built into the thermostat for room air con-
trol. The sensor monitors the room air conditions and
provides input signal(s) to the system controller. The
system controller manages the operation of the A/C
unit consistent with the set points entered.
As an option, the temperature sensor may be
shipped loose for fi eld installation in the room to be
conditioned. Refer to the electrical drawing supplied
with your unit for details specifi c to your system.
Ceilair Model OHS-024-AHU
Shown for Reference
(Access Panels Removed)
