Part 3 - S
yst
em Design and Ins
talla
tion
Amazon Unitario Top Discharge
167
Table 3-6.2: Vertical drain piping diameters
PVC piping
Nominal diameter
(mm)
Capacity (L/h)
Remarks
PVC25
25
220
Branch piping only
PVC32
32
410
PVC40
40
730
Branch or main piping
PVC50
50
1440
PVC63
63
2760
PVC75
75
5710
PVC90
90
8280
6.4 Drain Piping for Units with Lift Pumps
Drain piping for units with lift pumps should take account of the following additional considerations:
A downward sloping section should immediately follow the vertically rising section adjacent to the unit, otherwise a
water pump error will occur. Refer to Figure 3-6.7.
Air vents should not be installed on vertically rising sections of drain piping, otherwise water may be discharged
through the air vent or water flow may be impeded.
Figure 3-6.7: Downward sloping section of drain piping
6.5 Drain Piping Installation
Notes for installers
Installation of the drain piping should proceed in the following order:
Indoor unit installation
Drain piping installation
Watertightness test
Drain piping insulation
Caution
Ensure that all joints are firm and once the drain piping is all connected conduct a watertightness test and
water flow test.
Do not connect air conditioner drain piping to waste, rainwater or other drain piping and do not let air
conditioner drain piping come into direct contact with the ground.
For units with drain pumps, test that the drain pump functions properly by adding water to the unit’s drainage
pan and running the unit. To allow inspection and maintenance, the pipe clamps shipped with units should be
used to attach drain piping to indoor units – adhesive should not be used.
