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IM 817-4
5
For direct expansion (DE) coils the unit is supplied with a Low
Refrigerant Temperature Sensor (T4 - capillary sensor), that is
located on the leaving air side of the direct expansion coil. T4
cuts out below 34
o
F ± 2
o
F and automatically resets above 38
o
F ±
2
o
F. Responds when any 15% of the capillary length senses these
temperatures.
6
For Direct Expansion (DE) coils the unit is supplied with a 40 VA,
24 volt, NEC class 2 transformer, for 24 volt power (X2), with a
factory installed 5 minute timer delay relay (TDR) (located inside
Unit Power Box).
It is the responsibility of the Automatic Temperature Control
supplier to ensure that T4 and R4 are incorporated properly to
protect the unit.
Making Control Connections
Controls by Others Components
Daikin unit ventilators come with factory installed components and
wiring. It facilitates the field hookup of controls by others, capable
of providing the standard ASHRAE II cycle that are compatible with
these factory installed and pre-wired components.
It is the responsibility of the Automatic Temperature Control
supplier to ensure the controls operates correctly and protect
the unit.
Controls by others option consists of the following components which
are factory provided and wired where indicated:
1 Unit Main Power “On-Off” switch – disconnects main power to
the unit. Non-fused power interrupt switch (S1)
2
Fan motor, auto transformer and control transformer have the hot
line(s) protected by factory installed fuse(s).
3
Three (3) speed HIGH-MEDIUM-LOW-OFF motor fan speed
switch (SW2), wired to auto transformer (X1), to provide fan
speed/air delivery.
4
Factory installed Low Air Temperature (limit T6 - freezestat) across
leaving air side of hydronic heating coil. Cuts out below 38
o
F ±
2
o
F and automatically resets above 45
o
F ± 2
o
F. Responds when
any 15% of the capillary length senses these temperatures.
It is the responsibility of the Automatic Temperature Control supplier
to ensure the T6 freezestat is incorporated properly to protect the unit.
Figure 118 - Controls by Others Unit Component Locations
Figure 119 - Controls by Others Unit Power and Junction Box
Connection Location
1
2
3
4
5
6
6
Motor
Auto Transformer
Fuses
High-Med.-Low-Off
Motor Speed Switch
Switch
Junction Box
Terminal Strip
Electric Power
Wire Opening
in Back of Box
CAUTION
CAUTION
CAUTION