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31. 08. 21. Document Number 671746
Nuaire | Western Industrial Estate | Caerphilly | CF83 1NA | nuaire.co.uk
BPS (V/T)-ES
Installation Manual
11.5 Coils
Coils should be connected to ensure that full counter flow exists i.e. the
entering airflow meets the return connection.
All coils should be connected with the flow at the bottom and the
return at the top unless otherwise advised. Drain and bleed valves are
located on the coil, others may be required in the system pipe-work
depending on the installation.
Frost protection must be incorporated on shut down and fresh air
conditions to avoid coil freezing. Ideally, where the system is at risk of
frost damage, the addition of a proprietary antifreeze solution to the
water is recommended.
Pipe-work connections should be made to the unit using appropriate
techniques, and must be independently supported. The connections
should be pressure tested.
All coils sit in a common drip tray connected to the pre-fitted
condensate pump.
The coil panel has been pre-drilled and fitted with appropriate
grommets for pipe connections. Do not drill or cut the unit casing for
this purpose.
Coils should have their finned surface examined for accumulation of
dirt, lint and biological contaminants or similar. If necessary, wash
down affected areas with a mild detergent solution and a soft brush.
Care should be taken not to damage the finned surface, and any
cleaning fluids should be rinsed away with water.
A compressed air line may be used to blow out any solids between
fins. Do not probe the coil fin block with metal objects as damage
may cause leaks. Drain lines should be checked to ensure that they
are unobstructed and free draining. Drain pans should be flushed out
periodically to remove contamination.
The unit application may require particular attention to this item –
Check with Building Management personnel for details.
11.6 Plate Heat Exchanger
The recuperator block is normally protected from dust and
contamination by upstream pre-filters. It is possible to clean the unit
with compressed air in the case of dust deposits or by spraying with a
mild detergent solution for grease deposits.
Solvents, strong alkaline, acidic or any products that may be aggressive
to aluminium or plastics should not be used. Do not use cleaning water
over 50°C.
Drain lines should be checked to ensure that they are unobstructed and
free draining. Traps should be checked that they are fully primed and
functioning.
Drain pans should be flushed out periodically to remove contamination,
and chemical treatments may be used to provide protection between
service visits.
The unit application may require particular attention to this item –
Check with Building Management personnel for details.
11.7 Thermal Wheel
After the 2-3 weeks of operation, and at least once per year, ensure the
following maintenance is performed.
•
Check that rotor is vertical and centred in casing. Adjust vertical
and horizontal position if needed.
•
Check the thermal wheel spins freely.
•
Adjust sealing to ensure contact with the rotor and side plates.
Replace brush sealing if it is worn.
•
Check that motor bracket is in 20-45° angle from horizontal line.
•
Adjust length of drive belt if needed.
•
Check condition of belt and belt lock (joint).
20-45°
40
Thermal Wheel Belt
If the unit contains a thermal wheel heat exchanger, please ensure
that the rotation sensor is aligned with the sensing studs, as this
can become misaligned during transport / installation thus causing
a fault signal.
Experience shows that clogging of heat exchangers is not expected
in normal cooling and air-conditioning systems. However, if deposits
accumulate on the exchanger when used for special applications, it can
be cleaned as follows:
Remove dust and fibres with a soft brush or vacuum cleaner. Use
caution when blowing dirt out with compressed air to avoid damage to
the wheel. Keep at a distance!
Oils, solvents etc. can be removed with hot water (max. 70 °C) or
grease-removing solvents or immersion.
11.8 Legionella Check
Legionella risk management should be undertaken by a competent
person appointed by the duty holder in accordance with the latest
edition of the HSE approved code of practice L8 Legionnaires’ disease,
the control of legionella bacteria in water systems. Particular attention
should be given to:
•
Cooling coil.
•
Thermal Wheel.
•
Drain trays.
•
Water reservoirs.