IM 830-6
22 www.DaikinApplied.com
For 2-Pipe Chilled Water/Hot Water Systems
Install Water-in Temperature Sensor (OCT)
After making the piping connections, securely attach and
insulate the water-in temperature sensor (OCT) to the water
coil supply line (refer to
"Typical Piping Arrangements" on
). The sensor should be located on the water supply
line in an area where there is continuous water flow. The
sensor hangs loose in the same end compartment as the coil
connections. This sensor must be attached correctly for proper
unit operation.
WARNING
!
Water system under pressure. Keep face and body parts well away
from vent. Water pressure can result in severe personal injury.
This unit has an auto air vent.
1. To vent manually at initial operation: unscrew knurled head
(counter-clockwise) one or two turns. After manual venting,
tighten (clockwise) knurled head firmly. The auto vent will
work automatically.
2. The first time it is put into operation, a few drops of water
may escape, afterwards the auto vent will be tight.
3. If dirt has entered the knurled head, disassemble clean
and screw back in firmly (a built-in check valve will prevent
leakage).
CAUTION
!
Figure 44: Auto Vent and Drain Plug (Chilled Water Coil Shown)
Vent
Drain Plug
Suggested Condensate Trapping
Daikin cooling unit ventilators are designed for condensate
removal into a condensate disposal system. Do not connect
the unit drain connection so that condensate exits to
the outside and/or is exposed to freezing temperatures.
Installer is responsible for any damage that might be
caused from freezing condensate
. In applications with an
end compartment auxiliary drain pan, see the installation
instructions shipped with the auxiliary drain pan itself.
NOTICE
Each unit application is unique. Trapping may vary, or may not
be required for some applications.
Consideration should be given to trapping when a pressurized
air system is providing air to the unit. The condensate trap
provides for discharge of water from the unit ventilator drain pan
during the cooling mode, while the water seal (water level in the
condensate trap), prevents the flow of air from the unit ventilator
end compartment into the coil section during normal operation.
Improper trapping can lead to several problems. If the trap
is too tall, negative pressure will prevent drainage, causing
condensate backup. If the trap is too short the seal will be
destroyed or nonexistent, producing the same effect as a non-
trapped system.
The trap should be constructed of 7/8" clear plastic piping.
The condensate piping from the drain trap must be sloped
to facilitate proper drainage. The clear plastic trap should be
clamped and removable for cleaning. It may be necessary to
manually fill the trap at system start-up, or to run the unit for
sufficient time to build a condensate seal. The condensate trap
and condensate piping drainage should be free of any foreign
debris. Foreign debris can prevent proper operation resulting in
condensate buildup.
Figure 45: Recommended Condensate Piping
A
C
⅞" I.D. Clear Plastic
B
Drain Pan
Figure 46: Condensate Drain Static Pressures
A
B
C
High Static
1½"
3/4"
3⅛"
Figure 47: Condensate Drain Viewed from Bottom of Unit with
Hinged Access Door Open
