1. Heat exchanger application
The BLU series air-water heat exchangers
described in this manual are designed and built
to cool the air inside electrical switchboards/
enclosures in order to protect components
sensitive to thermal shock. They also provide
IP55 ingress protection against contaminating
and aggressive/corrosive substances.
1.1 Intended use
The BLU heat exchanger must be used:
- For cooling electrical switchboards
- Within the temperature and voltage-supply
limits indicated on the data plate of the heat
exchanger and also given in table F.12 of this
manual
- At a sufficient distance from any heat sources
- With water which meets the chemical and
physical properties given in the table in chapter
7.1
- On switchboards with IP55 rating or higher.
If these requirements are not respected,
excessive condensation build-up may occur.
As a consequence, cable entry points or any
other openings in the enclosure should be well
sealed.
To ensure correct operation, the specified
scheduled maintenance operations (see section
11) must be performed regularly. Incorrect or
careless use may cause irreparable damage to
the heat exchanger and may lead to hazardous
situations.
1.2 Improper use
The BLU heat exchanger must not be used:
- Under conditions other than those described in
section 1.1
- With the doors of the electrical switchboard open,
or installed on enclosures without a minimum IP55
rating, due to excessive condensate formation
- With the temperature set below the dew point of
the ambient air
-
In
potentially
explosive
atmospheres
- In potentially inflammable atmospheres
- With the condensate line closed or blocked off, or
in any case in which the condensate is not allowed
to run off freely
- Without the front panel
- With the components in the switchboard installed
in such a way as to obstruct the internal air flow
2. Supply
Inside the packaging you will find:
1 Air-water heat exchanger
1 Installation, operation and maintenance
manual
1 CE conformity certificate
1 Test certificate
1 A4 drilling template
1 Installation kit, containing (F.02 and F.03):
- Flanged nuts
- Flat washers
- Grub screws
1 Self-adhesive seal (F.02 and F.03)
1 Runoff pipe (BIT25) (F.05)
1 Condensate runoff pipe elbow joint BIT (F.05)
2 Eyebolts for handling (F.01)
3. Updates
Pavarini Components reserves the right to update
its products and the corresponding manuals based
on technical progress without prior notice. Please
note that at the time of sale, this manual and the
corresponding product may not be considered
inadequate only because they are not subject to
the above-mentioned progress.
4. Technical features
(figures F.12 and F.13)
The unit's technical features and CE marking
are given on the data plate attached to the heat
exchanger.
5. Transport and handling
During transport and storage the heat exchanger
must not be exposed to temperatures above
70°C or below -20°C. Upon receipt, check that
the packaging has not been damaged during
shipping.
To lift the heat exchanger in a safe manner the
two supplied M6 eyebolts may be used; these
should be fitted into the threaded inserts located
on the top of the heat exchanger (figure F.01).
6. Installation
Installation of the unit should only be performed
by qualified and authorised personnel.
The heat exchanger must be installed with the
enclosure air intake hole in the highest possible
point.
Ensure the fixing elements and couplings will not
interfere with the equipment inside the enclosure
itself.
If the cooling unit is to be installed on a door,
make sure the door can take the weight.
Install in a vertical position – maximum permitted
deviation from the vertical is 2°.
Disconnect power before starting any work
inside the switchboard.
The heat exchanger must be installed on the
outside of the electrical enclosure. Drill the holes
and make the necessary cuts in the enclosure
(figure F.03) using the drilling template supplied
with the unit. If required, fit the sealing strip on
the heat exchanger on the side connected to
the enclosure and follow the assembly diagram
(figure F.03).
or
corrosive
7. Water connection
- Connect the water supply with a threaded
union.
- Check whether it is possible to connect to an
existing circuit or to a refrigerated water supply.
- Check that the circuit pressure is not greater
than the permitted value.
- Check that there are no leaks from the pipes
when charging the circuit with water.
7.1 Chemical parameters of the water in the
circuit
For correct operation of the heat exchanger, and
to prevent corrosion, the water used in the circuit
must respect the limits given in the table below:
Parameters
pH
Carbonate hardness
Dissolved carbon dioxide
Combined carbon dioxide
Aggressive carbon dioxide
Sulphides
Oxygen
Chloride ions
Sulphate ions
Nitrates and nitrites
COD (Chemical Oxygen Demand)
Ammonia
Iron
Hydrological data
Limits
7 - 8.5
3 - 8 °dH
8-15 mg/dm
3
8-15 mg/dm
3
0 mg/dm
3
< 10 mg/dm
3
< 50 mg/dm
3
< 50 mg/dm
3
< 250 mg/dm
3
< 7 mg/dm
3
< 5 mg/dm
3
< 5 mg/dm
3
< 0.2 mg/dm
3
7
Manganese
Conductivity
Dry residue
Potassium permanganate
Suspended substances
8. Condensate runoff pipe
The condensate which, depending on the
ambient temperature and humidity conditions,
forms on the heat exchanger with finned tube
which cools the enclosure air, is not a malfunction
but a normal feature of the unit's operation. This
condensate is taken outside through a pipe at
the bottom of the heat exchanger.
A transparent Ø 12X2 plastic pipe must be
connected to this outlet (figure F.06, F.07).
A 2.5 m plastic runoff pipe must be connected to
BIT machines for this discharge (figure F.05).
To do this, the pipe must be cut to the correct
length to span the distance between the metal
pipe coming out of the machine and the edge
of the enclosure roof. This section of pipe must
then be coupled to the remaining length of pipe
using the supplied elbow joint in order to bring
the condensate to the base of the enclosure. This
plastic pipe can be connected to another one
with the same diameter to carry the condensate
to another point, allowing it to be discharged in
an area where there can be no slipping hazard
for personnel. In this case, make sure the
condensate flows without any hindrance. Avoid
horizontal lengths of more than 0.5 metres, uphill
sections and the accidental formation of traps
(figure F.06). The end of the condensate runoff
pipe must always be free and never underwater.
The end of the condensate runoff pipe must
therefore never be placed inside a condensate
collection container (figure F.07). Using the
heat exchanger with the doors of the enclosure
open would generate an excessive amount of
condensate; this is therefore not an authorised
condition of use (figure F.08). To avoid this
problem we suggest using a position switch on
the door that will stop the heat exchanger if the
door is opened.
9. Electrical connection
9.1 Safety
Warning! Caution! Electrical connections
must only be performed by specialised and
authorised personnel.
Check that there is no power to the switchboard
and that the supply voltage corresponds to the
characteristics given on the heat exchanger's
data plate. In order to ensure protection of
the power supply, use delayed action fuses/
switch disconnectors or magneto-thermal cut-
off switches (e.g. RCDs) of the values indicated
(figure F.12). Connect the cables as indicated
in the wiring diagram, taking care to correctly
identify the individual wires.
9.2 Models with autotransformer
(BLUA0GX0A-BLUA5GX0A)
These two-phase models can operate with two
different supply voltages: 440V 2~ 50-60Hz and
400V 2~ 50-60Hz.
The heat exchanger is factory set for a 400V 2~
50-60Hz power supply. If you wish to power the
heat exchanger with a 440V 2~ 50-60Hz supply,
the panel must be opened and the connection
modified as follows: move the male faston 31
from the female faston 31A to the female faston
31B (Figure F.11).
ENG
< 0.2 mg/dm
3
< 2200 µS/cm
< 500 mg/dm3
< 25 mg/dm3
< 3 mg/dm3