Carrier MODU-PAC 50DF - Manual (Page 19)

50DF
m
Application data
Duct connections — Concentric
ducting requires a field-fabricated tran­
sition piece external to the unit.
Field conversion to side duct connec­
tions is possible on all models except
those utilizing power exhaust. Units
using economizer with side duct con­
nections require accessory conversion
kit.
Head pressure control — The refrig­
eration systems in all units are inherently
designed to operate efficiently at out­
door air temperatures down to 35 F
without extra controls or modifications.
An outdoor air temperature activated
fan cycling thermostat is factory in­
stalled in each unit, as required, to
accomplish this.
To permit unit to operate at outdoor
air temperatures below 35 F, a Motor-
master® head pressure control may be
field installed. This control varies the
outdoor air fan speed to maintain
correct condensing temperature at out­
door air temperatures down to -20 F.
A Motormaster accessory package is
available for each unit and voltage
configuration.
Sound and vibration — Operation of
rooftop units on modern, light roof
construction may induce sound and
vibration problems. On each individual
job, unit location, vibration isolation,
sound attenuation and local outdoor
noise codes may require special con­
sideration. For installation information,
refer to ASHRAE Systems Handbook,
Chapter 35, Sound and Vibration and
Carrier application literature.
THRU-THE-SIDE
DUCT CONNECTIONS
CONCENTRIC DUCT CONNECTION
NOTE: Thru-the-side connections are not
applicable to units with power exhaust
option.
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