Lennox ROOFTOP FLEXY FXK 55, Installation, Operating And Maintenance Manual

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HEATING : HOT WATER COIL
FLEXYII_WSHP-IOM-1307-E - 57 -
HYDRAULIC CONNECTIONS
Hot water coils offer fully modulating control through the
use of a 3 way valve. The hot water coil, connections and
valves are all tested at pressure of 15 bars. Frost protection
is provided by forcing the opening the 3 way valve when
supply temperature from hot water coil falls below 8°C and
by stopping the outdoor fan when that supply temperature
falls below 6°C. In addition to that, the 3 ways is also
opened at 10% value if the outdoor temperature falls below
an adjustable value.
Hot water coils are always factory fitted, wired and fully
tested, prior to shipment.
Hot water coil includes automatic purge system.
The hot water coil is fitted with a three way proportional
valve and two isolating shut off valves. Two spanners must
be used to tighten the connections. One spanner must
maintain the valve body when connecting the pipe-work to
the main. Failure to do so may damage the pipes joints and
invalidates the warranty.
Filling up and starting the system
- Adjust the control for Heating by reducing the
simulated ambient temperature down to 10°C
- Check that the red indicators located under the valve
actuator are moving correctly with the signal.
- Fill the hydraulic system and bleed the coil using the
air vents. Check incoming hot water.
- Check the various connections for possible leaks
FREEZE PROTECTION
1) Glycol for freeze protection.
Check the hydraulic system contains Glycol for protection
against freezing.
GLYCOL IS THE ONLY EFFECTIVE PROTECTION
AGAINST FREEZING
The antifreeze must protect the unit and avoid icing under
winter conditions.
WARNING: Mono-ethylene glycol based fluids may
produce corrosive agents when mixed with air.
2) Drain the installation.
You must ensure that the manual or automatic air bleeders
have been installed on all high points in the system. In
order to drain the system, check that all the drain cocks
have been installed on all low points of the system.
HOT WATER COILS FROZEN DUE TO LOW AMBIENT
CONDITIONS ARE NOT COVERED BY THE
WARRANTY.
ELECTROLYTIC CORROSION
Attention is drawn to the corrosion problems resulting from
electrolytic reaction created by unbalanced earth
connections.
ANY COIL DAMMAGED BY ELECTROLYTIC
CORROSION IS NOT COVERED BY THE WARRANTY