Lennox FLEXY FX 025 Application Manual page 7

GENERAL DESCRIPTION
Alternate defrost
Because, this new rooftop has been designed to reduce life cycle
cost, the alternate defrost is a standard feature.
When one circuit is in defrost the other is still running in heat-
pump mode reducing the use of costly electric heater.
This unique feature on the market place comfort the FLEXY FX
as leader in terms of low life cycle cost.
Dynamic defrost (Under patent)
FLEXY FX is featuring the «dynamic defrost» concept.
In general rooftop start defrost cycle when the outside temperature
is bellow a certain value and repeat the cycle periodically.
This results sometimes in starting an expensive defrost cycle
when it is very cold outside but very dry, in other words when the
coil is not frozen.
After many tests in the Lennox laboratory, it was found that it is
possible to exactly know if the coil is frozen, by analyzing the tem-
perature difference between the coil and the outside temperature.
With this built-in feature of the CLIMATIC 50, Lennox insures to
start a defrost cycle only when necessary, hence saving energy.
EASY TO INSTALL AND SERVICE
STANDARD FEATURES
Light unit
FLEXY FX has been designed to be as light as possible to avoid
constraints.
PLUG and PLAY Unit
All options are factory installed on the unit, which means that they
are ready for use on installation, ensuring that the time spent
on site is minimised, reducing the installation effort, which can
result in cost savings.
Bottom entry (through the base) for electrical power and Hot
Water lines are available as standard.
FLEXY FX should be powered by 400 V, 3phases, 50 Hz.(no
neutral needed).
Application Guide • FLEXY FX-AGU-1112-E
Circuit breakers
To improve the safety of the FLEXY FX and extend its life, cir-
cuit breakers protect against over-loading, over intensity and a
disconnected supply phase. Maintenance is also improved as
there is no requirement to change fuses. The electrical panel is
manufactured in accordance with EN60204-1 (1998) electrical
directive.
Numbered wires
All wires and connectors are numbered as shown on the electrical
drawing to facilitate maintenance and diagnostic.
Variable Pulley
For cases where the actual external static pressure or air fl ow
on a particular project is different from what is specifi ed on an
order, LENNOX has enhanced the FLEXY FX rooftop by providing
an adjustable pulley. The installer can easily and quickly adjust
the air fl ow within a 20% window without moving the mounted
fan motors. This variable pulley provides fl exibility and peace of
mind during commissioning.
EU4 / G4 grade - Disposable Filters
Ensuring easy service and maintenance. On start-up we recom-
mend that you change the throwaway fi lters for replaceable
washable fi lters, with metal frames.
BE CAREFUL TO THE FILTER FIRE CLASS
RELATED TO THE LOCAL RULES
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