4
M
INI
-S
PACE
EC I
NSTALLATION
, O
PERATION
AND
M
AINTENANCE
M
ANUAL
heating coil is factory installed in the supply air stream to heat
the supply air. A valve is provided to control the fl ow of hot gas
through the coil to maintain the correct reheat temperature.
1.4.4 Coil
The cooling and optional hot gas reheating coils are aluminum
fi nned/copper tube construction. The coils are leak tested
and cleaned before installation by the factory.
1.4.5 EC
Fan
The unit is equipped with a high effi ciency Electronically
Commutated (EC) fan. EC fans have a brushless motor
equipped with permanent magnets and permanently
lubricated ball bearings. The fan impellers are backwards
curved and attached to the rotor casing. The fan is balanced
and aerodynamically optimized to minimize vibration.
The fan does not use a drive belt. Fan speed is variable via a
0-10 VDC signal from the system controller. The fan motor is
equipped with integral electronics such as thermal protection,
inverters or fi lters. The fan will not produce AC inverter whine.
1.4.6 Temperature/Humidity
Sensor
As a standard for room air control, a temperature/humidity
(T/H) sensor is factory mounted in the return air stream.
The (T/H) sensor monitors the return air conditions and
provides input signal(s) to the system controller to manage
the operation of the A/C unit consistent with the setpoints
entered in the system controller. As an option, sensor(s) may
be shipped loose for fi eld installation. Refer to the electrical
drawing supplied with your unit for details specifi c to your
system.
1.4.7 Controller
Mini-Space EC units have a STULZ
E²
Series Microprocessor
Controller that provides these general features:
•
Full alarm system
•
Input/output status monitoring
•
Full integrated control of cooling
•
Multi-system control and remote communica-
tion with building management systems
The
E²
controller is mounted inside the unit electric box. User
interaction is through a graphic terminal mounted on the front
of the unit. It has a backlit liquid-crystal alphanumeric display
and a set of function keys to navigate through the controller
menus and adjust operating parameters.
A customer-provided BMS may be used to directly interface to
the
E²
controller. Operating instructions for the
E²
controller
are provided in the
STULZ E² Series Microprocessor
Controller Operators Manual
.
Refer to that manual for
detailed instructions on operating the system controller.
1.5 Optional
Equipment
1.5.1 Humidifi er (Optional)
Mini-Space EC systems may utilize an optional electrode
steam humidifi er. The humidifi er is factory installed inside
the air conditioner and includes fi ll and drain valves and
associated piping. Operation of the humidifi er’s fi ll and drain
cycles is based on water conductivity and is maintained by the
humidifi er controller. An operating manual for the humidifi er
is provided with the unit under separate cover. Refer to that
manual for detailed information about humidifi er operation.
1.5.2 Condensate
Pump
An optional condensate pump may be used to remove
condensate from the air conditioner and fl ush water from the
humidifi er. An internal overfl ow safety switch is wired to the
system controller to automatically shut down the precision
A/C system should an overfl ow occur.
1.5.3 Smoke
Detector
Optionally mounted in the return air stream, a smoke detector
is used to sense the presence of smoke and signal the
controller when a smoke alarm condition exists.
1.5.4 Firestat
Optionally mounted in the return air stream, a fi re detector
senses high return air temperature and signals the controller
when a fi re alarm condition exists.
