UV light reset switch
When equipped with UV lights, the UV light reset
switch must be switched ON whenever the UV lights
are disabled due to opening the evaporator, supply
fan, or filter cabinet door.
See Figure 26 and Figure 27 for location.
Field tubing
The unit could have several factory installed static
pressure transducers that are required for certain
unit types and sequences.
These factory installed transducers must have field
provided pneumatic tubing installed. The pneumatic
tubing should be 3/16 in. inside diameter (ID) and
connected to the high side port of the transducers.
Route the field provided tubing to the appropriate
location dependent on the transducer and the
function.
Discharge air static pressure transducer
•
A unit can be ordered configured for variable
air volume (VAV), in which a discharge air
static pressure transducer is factory installed.
•
Route the field provided pneumatic tubing
from the high side port of the transducer and
connect it to the discharge air static probe
located in the supply ductwork.
•
The ideal location for the discharge air static
probe is two-thirds of the way between the
unit outlet and the first duct take-off or tee.
•
The discharge air static pressure sensor is
located inside the economizer section on the
vertical upright on the front wall.
Building static pressure transducer
•
A unit can be ordered with a factory installed
exhaust damper that is capable of removing
excess building static pressure. If the unit was
ordered with an exhaust damper, a building
static pressure transducer is factory installed.
•
Route the field provided pneumatic tubing
from the high side port of the building static
pressure transducer to the building static
pressure probe.
•
The ideal location for the building pressure
probe should be in an interior closet with
little to no traffic and an undercut door.
Locations of the probe can vary greatly with
each building type.
•
The building static pressure sensor is located
inside the economizer section on the vertical
upright on the front wall of 25 ton to 50 ton
units. On 60 ton to 80 ton units the building
static pressure sensor is located inside the
control panel.
Outdoor pressure reference
•
If a unit has either of the previous pressure
transducers installed, an outdoor pressure
reference is needed (Figure 32).
•
An outdoor pressure reference kit is shipped
loose in the unit for field installation.
Figure 32: Outdoor pressure reference assembly
•
On units with outside air hoods, the
pneumatic tubing is always installed on the
side of the outside air hoods.
•
On units without outside air hoods, the
pneumatic tubing placement is decided by the
contractor.
•
Refer to the instructions provided with the
outdoor pressure reference for proper
installation.
Tempmaster
®
Omni™ Premier 25 Ton to 80 Ton Rooftop Units Installation and Maintenance Guide
75
Tempmaster
