Carrier 40MBDQ09 3 Series Installation Instructions Manual page 9

INSTALLING DUCTWORK
Connect the return and supply ducts to the duct collars provided on
the unit. Adequate distance between the return and supply diffusers
should be maintained to avoid short circulation of air within the space.
The filter is located on the return side of the unit, on the rear or
bottom depending on the return air inlet arrangement.
Fig. 13 − Installing Duct
OUTSIDE AIR CONNECTION
If necessary, an outside air connection knockout is located on the side
of the unit downstream of the air filter. It is recommended to field
supply and field install a booster fan on the duct work used for outside
air. A booster fan may be powered by the connection on the PCB
board CN43. The maximum input for the motor is 200W. The output
of the NEW FAN will be active while the indoor fan is active.
NOTE: The amount of outside air is dependent on different
factors as the booster fan, outside air duct work type and length,
static pressure, conditions, etc..
Ø4.92" (125mm)
Fig. 14 − Outside Air Connection
CONDENSATE PIPE INSTALLATION
The unit is supplied with a 1 1/4−in. OD drain connection to
connect copper or PVC drain piping. When installing condensate
piping, follow these recommendations:
S Install drains to meet local sanitation codes.
S The Ducted Style Indoor unit is supplied with a condensate lift
pump that is capable of lifting water 29.5in. (750mm).
S The highest point in the condensate piping should be as close to
the unit as possible (see Fig. 17).
S Condensate piping should slope downward in the direction of
condensate flow, with a minimum gradient of 1/100.
S When multiple units are connected to a common condensate
drain, ensure the drain is large enough to accommodate the
volume of condensate from all units. It is also recommended to
have an air vent in the condensate piping to prevent air lock.
A150671
Ø6.3"(160mm)
9
S Condensate piping must not be installed where it may be
exposed to freezing temperatures.
S To prevent the pipe from sagging, space hanging wires every
39−59in. (1−1.5m).
S If the outlet of the drainpipe is higher than the body's pump
joint, provide a lift pipe for the exhaust outlet of the indoor unit.
The lift pipe must be installed no higher than 21.7in. (55cm)
from the ceiling board. The distance between the unit and the lift
pipe must be less than 7.9in (20cm). Incorrect installation could
cause water to flow back into the unit and flood.
S To prevent air bubbles, keep the drain hose level or slightly tiled
up <3in. (75mm).
1. Cover the drain hose with heat insulation to prevent
condensation and leakage.
2. Attach the mouth of the drain hose to the unit's outlet pipe.
Sheath the mouth of the hose and clip it firmly with a pipe
clasp (see Fig. 15).
Drain hose
Drainpipe
Pipe clasp
connecting port
Fig. 15 − Indoor Drainpipe Installation
Fig. 16 − Condensate piping without a pump
Ceiling
Fig. 17 − Condensate piping with a pump
When connecting multiple drainpipes, install the pipes as
illustrated on Fig. 18.
0-53cm
(20.8")
≥10cm
(4")
Fig. 18 − Connecting Multiple Drain Pipes
Insulation
1-1.5m
<20cm
(39-59")
Lean over 1/50
(7.9")
0 - 75mm
(3")