Drain Piping Work - Daikin FTQ18TAVJUA Installation Manual

• Use of oxygen could result in an explosion resulting in serious
injury or death. Only use dry nitrogen gas.
• Refrigerant gas may produce toxic gas if it comes in contact
with fire such as from a heater, stove or cooking device.
Exposure to this gas could cause severe injury or death.
• Do not use flux when brazing refrigerant piping. Therefore,
use the phosphor copper brazing filler metal (BCuP) which
does not require flux.
Flux has an extremely negative effect on refrigerant piping
systems. For instance, if chlorine based flux is used, it will
cause piping corrosion. Flux containing fluorine will damage
refrigerant oil.
6.

DRAIN PIPING WORK

The coil drain pan has a primary and a secondary drain with 3/4"
NPT female connections. The connectors required are 3/4" NPT
male, either PVC or metal pipe, and should be hand tightened to
a torque of no more than 37 in-lbs. to prevent damage to the
drain pan connection. An insertion depth of approximately 3/8"
to 1/2" (3-5 turns) should be expected at this torque.
1. Ensure drain pan hole is not obstructed.
2. To prevent potential sweating and dripping on to finished
space, it may be necessary to insulate the condensate drain
line located inside the building. Use Armaflex® or similar
material.
A secondary condensate drain connection has been provided
for areas where the building codes require it. Pitch all drain lines
a minimum of 1/4" per foot to provide free drainage, or as required
by local code. Provide required support to the drain line to prevent
bowing. If the secondary drain line is required, run the line
separately from the primary drain and end it where condensate
discharge can be easily seen.
• Water coming from secondary line means the coil primary
drain is plugged and needs immediate attention.
• Insulate drain lines located inside the building or above a
finished living space to prevent sweating. Install a condensate
trap to ensure proper drainage.
• Some installation may require a field fabricated or field
supplied secondary drain pan under the coil cabinet
enclosure. The installation must include a "P" style trap that
is located as close as is practical to the evaporator coil See
Figure 15 for details of a typical condensate line "P" trap.
• Trapped lines are required by many local codes. In the
absence of any prevailing local codes, please refer to the
requirements listed in the uniform mechanical building code.
A drain trap in a draw-through application prevents air from
being drawn back through the drain line during fan operation
thus preventing condensate from draining, and if connected
to a sewer line to prevent sewer gases from being drawn
into the airstream during blower operation.
English
Air Handler
POSITIVE LIQUID
SEAL REQUIRED
AT TRAP
Observe the following guidelines when installing concentrated
drain piping. Select the thickness of the concentrated drain piping
to reflect the capacity of the machine to which it will be connected.
(Install a drain trap for each indoor unit.) See Figure 16.
At least 4 in.
Concentrated drain piping
(Use a downward slope of at least 1/100.)
Figure 16
• If secondary drain is not installed, the secondary access must
be plugged.
Condensate drain traps with an open vertical Tee between the
air handler and the condensate drain trap can improve
condensate drainage in some applications, but may cause
excessive air discharge out of the open Tee. Daikin does not
prohibit this type of drain but we also do not recommend it due
to the resulting air leakage. Regardless of the condensate drain
design used, it is the installer's responsibility to ensure the
condensate drain system is of sufficient design to ensure proper
condensate removal from the coil drain pan. Use of a condensate
removal pump is permitted when necessary. This condensate
pump should have provisions for shutting off the control voltage
should a blocked drain occur. See Auxiliary Alarm Switch section
for more details. A trap must be installed between the unit and
the condensate pump.
Drain
Connection
2" MIN.
Figure 15
3" MIN.
11