Variable speed drive compressors provide a
modulating cooling capacity range of 15–100%.
Compressor circuiting
The Premier unit is designed to achieve efficient
system capacity by using multiple compressors
and refrigeration circuits. With multiple circuits, if a
compressor should ever fail on one circuit, the other
circuit remains operational to work to maintain
occupied loads. This means a more reliable unit and
less equipment downtime.
Compressor sound blankets
Optional factory installed compressor sound
blankets can help to further reduce sound radiated
from the compressor. In applications such as
downtown areas, where acoustics are important,
sound blankets are especially helpful with reducing
outdoor unit sound.
Replaceable core filter driers
The optional replaceable core filter driers remove
moisture, dirt, and debris from the refrigeration
circuit in the event it is opened. Additionally, the
optional replaceable core filter drier helps to
maintain and optimize the unit's refrigeration
system.
Low ambient operation
Head pressure control is accomplished via a variable
frequency drive (VFD) motor controller rather than
an inefficient and noisy condenser fan damper.
By varying the speed of the condenser fan, better
control and quieter operation is obtained during the
colder months.
In low ambient mode, compressors have the
capability to operate down to -10.0°F and resume
cooling at -7.0°F, thereby giving customers an
improved envelope control.
Condenser fan motors
The condenser fan motors used on the units are
permanently lubricated open drip proof (ODP) type
to provide maximum durability through any season.
The roof above the condensers includes a drain
location to prevent pooling of water.
Condenser coils
Condenser coils are available to suit almost any
type of application. Post-coated aluminum fins are
available.
The use of an epoxy coated coil is recommended for
units installed in a corrosive environment.
Condenser coil protection
The unit is available with a wire mesh guard or
louvered hail guard for optimum coil protection.
Blank section
Sound attenuator
To meet customer specific requirements in sound-
sensitive applications such as theaters, libraries,
or hospitals, a sound attenuator is provided as an
option in the downstream section of the cooling
coil. Sound travels through the supply air duct
path, hence it needs particular attention. Contact
Tempmaster Application Engineering for application
specific requirements.
Humidifier
A humidifier option should be considered
for applications that have dry air and need
humidification in the occupied space. The unit
ships with a steam control valve, cast iron steam
traps, and an iron wye strainer and can be easily
connected on the bottom right-hand side of the
unit. An additional drain pan is provided in the
humidifier section for condensate removal.
Note:
Steam must be field provided.
Air blender
The unit has an option to install an air blender in the
pre-evaporator section to help improve temperature
control accuracy, mixing of outdoor air, and evening
of the air velocity profile.
Evaporator section
Evaporator coils
Interlaced, circuited evaporator coils are a standard
feature on all units. Copper tubes are internally
enhanced and expanded to bond with either
aluminum or copper fins. All coils are pressure
tested at the factory to meet the established
quality standards. Epoxy coated coils are optionally
provided as an enhanced feature to provide
substantial resistance to corrosion.
Modulating hot gas reheat
The unit has an option for modulating hot
gas reheat (HGRH). The HGRH system is an
efficient approach for moisture removal and
dehumidification of the space. Temperature and
humidity are efficiently maintained in the space,
reducing energy costs and improving customer
comfort.
Tempmaster
®
Omni™ Premier 25 Ton to 80 Ton Rooftop Units Installation and Maintenance Guide
16
Tempmaster