Drain Piping - Hitachi RPC-FSN3E Installation And Operation Manual

Drain piping

Flare Pipe Dimensions
Nominal
Diameters
1/4
3/8
1/2
5/8
4 DRAIN PIPING
4.1 GENERAL
C A U T I O N
• Do not create an upper-slope or rise for the drain piping, since
drain water will flow back to the unit and leakage to the room
will occur when the unit operation is stopped.
Incorrect: Upward Slope
Incorrect: Rising Part
• Do not connect the drain pipe with sanitary or sewage piping
or any other drainage piping.
• When the common drain piping is connected with other in-
door units, the connected position of each indoor unit must be
higher than the common piping. The pipe size of the common
drain pipe must be large enough according to the unit size and
number of unit.
1/25~1/100 Down Slope
CORRECT
Common Drain Piping
12
(mm)
Outer
A
+0/-0.4
Diameters
6.35 9.1
9.52 13.2
12.70 16.6
15.88 19.7
INCORRECT
Drain Piping connection
PMML0320A rev.2 - 09/2015
Thickness of Copper Pipes
Nominal Outer
Diameters Diameters
1/4 6.35
3/8 9.52
1/2 12.70
5/8 15.88
Flare Nut Dimensions
Nominal
Diameters
1/4
3/8
1/2
5/8
• Drain piping will require insulating if the drain is installed in a
location where condensation forming on the outside of drain
pipe may drop and cause damage. The insulation for the drain
pipe must be selected to insure vapor sealing and prevent
condensation forming.
• Drain trap should be installed next to indoor unit. This trap
must be designed to good practice and be checked with water
(charged) and tested for correct flow. Do not tie or clamp the
drain pipe and refrigerant pipe together.
N O T E
Install drainage in accordance with national and local codes.
After performing drain piping work and electrical wiring, check to
ensure that water flows smoothly as in the following procedure:
Checking Unit without Drain-up Mechanism
• Pour approximately 1.8 liters of water into the drain pan.
• Check to ensure that the water flows smoothly or whether no
water leakage occurs. When water cannot be found at the
end of the drain piping, pour another approximately 1.8 liters
of water into the drain pan.
N O T E
Pay attention to the thickness of the insulation when the left side
piping is performed. If it is too thick, piping can not be installed
in the unit.
(mm)
Thickness
0.80
0.80
0.80
1.00
(mm)
Outer
B
Diameters
6.35 17
9.52 22
12.70 26
15.88 29