Technical data

Condensate lift pumps
Lift pumps are included on FDT cassette, and FDR ducted
cassette. Please refer to the maximum allowable lift for
the relevant pumps. Condensate pumps are also included
on the KX Inverter Multi systems –models: FDT cassette,
FDR ducted cassette, FDTS single discharge cassette, FDTW
2-way cassette, and FDUM horizontal ducted unit.
Condensate piping
For units which include a condensate pump, it is important
to install the vertical section within the limitations detailed.
Where there is sufficient height within the ceiling void,
the pump can be utilised to raise the condensate water
to a height sufficient to ensure a positive downward
gradient to a gravity drain. This eliminates the requirement
for a secondary condensate disposal pump.
For units with a lift pump, it is essential the first horizontal
section and vertical lift are installed within the limitations
indicated in the piping diagram. This is to prevent too
much water being contained in the vertical lift, which
would flood back to the unit and overflow, when the
power is switched off.
Pipe termination - FDT & FDR
The pipe termination is of rigid polythene 25mm o.d.
FDT cassette and FDR ducted units include an insulated
flexible connection sleeve, complete with a securing clip,
which terminates to 25mm i.d., 32mm o.d.
Termination sizes for FDEN, FDKN & FDU
FDEN termination 20mm o.d.
FDKN termination 16mm o.d.
The above are flexible hoses with
serrated push on fitting.
FDU termination 32mm i.d. flexible
Gravity drain
The condensate gravity drain must be rigid heavy duty
PVC to BS3505 Class E. Alternatively, copper drain piping
can be used, which should be to BS2871 Part 1 Table-Y.
This should be connected in a similar way to the rigid
gravity drain piping. Care must be taken not to damage
or dislodge the pipe outlet from the unit.
The drain pipe must be inclined away from the unit at a
downward gradient of at least 1 in 50. Traps must not be
fitted (except for FDU – see note below). It may be
necessary to provide rodding access for cleaning purposes,
for a long condensate drain run.
Pipe insulation must be fitted if there is a possibility of
condensation forming on the outer surface of the drain
piping, or the connection fitting.
Avoid positioning the drain termination where unpleasant
odours, or gases, may enter the pipe, and subsequently
enter the conditioned space.
1. Do not provide air vent in the condensate drain.
2. Do not allow upward elevation.
3. Do not trap.
4. Do not terminate the drain where it can
become submersed.
5. Provide adequate support to condensate pipework to
avoid sagging.
27
Installation & recommendations - Condensate Drains
Air vent
Avoid riding across an elevation
Keep free from traps
Do not pipe under water
295 - 325mm 100mm or less
VP25 joint (field purchase)