BWT ET-NU 25 kW User manual

INSTALLATION AND OPERATING INSTRUCTIONS
To be read carefully and kept for future reference
FR | PAGE 1 - EN | PAGE 15 - DE | SEITE 29 - ES | PÁGINA 43
Heat exchanger
ET - NU25 - ET - NU40 - ET - NU60 - ET - NU90
ET - CA25 - ET - CA40 - ET - CA60 - ET - CA90
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1. TECHNICAL DATA ....................................................................................... 17
2. INSTALLATION OF THE HEAT EXCHANGER............................................... 17
2.1 Installation site......................................................................................................................17
2.2 Hydraulic connections .........................................................................................................17
3. ELECTRICAL WIRING.................................................................................. 18
4. STARTING UP THE HEAT EXCHANGER...................................................... 20
5. OPERATING CONTROLS ............................................................................. 20
6. WINTERIZING.............................................................................................. 21
7. TECHNICAL DATA ....................................................................................... 22
8. FOOT PRINT OF THE HEAT EXCHANGER .................................................. 25
9. FOOTPRINT OF THE PRESASSEMBLED HEAT EXCHANGER ..................... 26

1. TECHNICAL DATA
Unit MK1 MK2 MK3 MK4
Primary °C 90 45 90 45 90 45 90 45
Secondary °C 25 25 25 25
Power kW 27 8 43 12 58 17 95 27
Flow rate Primary m3/h 0.72 1.2 1.74 1.8
Secondary 4.5 5 6.5 11
Primary connections Threading 3/4ʺ
Secondary connections PVC union, female, solvent 50 to 63 mm
Operating temperature
Pool water 2 to 40 °C
Primary
water loop 45 to 90 °C
Max operating pressure Primary 2 bars
Secondary 1.5 bars
2. INSTALLATION OF THE HEAT EXCHANGER
2.1 Installation site
• Heat exchangers must be installed in accordance with the rules of the art and the standards in effect.
• The heat exchanger should be installed as close as possible to the boiler in order to minimise heat loss.
If this is not possible, you will need to lag the primary circuit pipes with thermal insulation.
• For optimum heat exchange, the ows in the primary circuit and secondary circuit must cross within the
exchanger.
• The heat exchanger must be connected directly to the boiler’s hot water production system. It should
under no circumstances be plumbed into an existing network (radiator circuit, residential hot water
supply circuit, etc.).
• To mount the heat exchanger, use the support plate as a template to mark out the 4 holes that need to
be drilled in the wall.
2.2 Hydraulic connections
schematic diagram of a
standard installation
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The heat exchanger was originally designed for a pool water ow from left to right.
The water from the boiler enters from the left, ows through the heat exchanger in the opposite direction
to the pool water and exits on the same side lower down.
The temperature sensor is inserted into the recess on the left-hand side of the heat exchanger (at the pool
water entry point).
To invert the direction of water ow, do the following :
• Unscrew both of the 3 part unions on the circulator and invert them. Screw the 3 part unions back together.
• Take the temperature sensor out of the housing on the left-hand recess and insert it into the corresponding
recess on the right hand side.
3. ELECTRICAL WIRING
Loosen the 4 screws to remove the cowling
Connect the terminals
• Red wire to live • Blue wire to neutral • Yellow/green wire to earth
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Live
Neutral
Earth
Filtration
contact
NO Slaving the exchanger
circulation pump to the
ltration pump.
If the circulation pump is not slaved to the ltration pump, shunt the two terminals using the shunt provided.
When a heating demand is detected the circulation pump will start up even if the ltration pump is not
running.
CAUTION:
To avoid heating of the termninals, ensure that the terminal screws are well tightened.
Plug the male connecter into the female connector.
CAUTION:
The heat exchanger seal ensures leaktightness of the heating circuit. The two nuts on the body of the heat exchanger
should under no circumstances be loosened. Failure to comply with this instruction could lead to cancellation of
guarantees.
Primary circuit
• The cross section of the primary circuit will be determined by the rate of ow into the heat exchanger
(refer to the technical specications of the various models).
IMPORTANT
When tightening (or loosening) the primary circuit connections on the exchanger’s brass unions, hold the unions steady
using a wrench to prevent any movement. Any rotation of the brass unions could damage the plastic body of the heat
exchanger and give rise to a leak, cancelling any guarantees.
Secondary circuit
• The secondary circuit is plumbed into the pool return line, preferably in by-pass, after the lter and
before the injection of any chemical products.
• Make the necessary provisions to cope with the risk of freezing during winter, notably ensure that it is
possible to drain the secondary circuit completely (by means of a drain valve mounted on the installation
or by loosening one of the unions on the heat exchanger).
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4. STARTING UP THE HEAT EXCHANGER
Once the exchanger is plumbed in and wired, do the following:
• Start up the ltration pump and make sure that there are no leaks on the hydraulic circuit.
• Open the isolating valves on the boiler’s primary circuit.
• Power up the heat exchanger. The digital display on the thermostat lights up, 888 blinks for a few
seconds, then the pool temperature is displayed.
• Move the control switch to ʺOnʺ.
• If the pool temperature is lower than the set point temperature, the indicator light on the switch is
illuminated indicating that the circulating pump is running.
Note : The indicator light is only illuminated while the circulating pump is running. Therefore, while the pool
water is at the desired temperature, it is normal for the indicator light to be out although the switch is set
to ʺOnʺ.
Changing the temperature set point:
Press the ʺSETʺ key and hold it down (less than 4
seconds), the value of the set point is displayed.
The set point can be modied using the ʺUPʺ and
ʺDOWNʺ keys once the ʺSETʺ key is released.
To increase the desired temperature, press the
ʺUPʺ key, press the key repeatedly until the desired
temperature is displayed (maximum 45° C), then
press ʺSETʺ or wait 10 seconds.
To decrease the desired temperature, press the
ʺDOWNʺkey, press the key repeatedly until the
desired temperature is displayed (minimum 15° C),
then press ʺSETʺ or wait 10 seconds.
While the snowflake is lit up, the device is running
normally
Once the desired set point is displayed, wait for a few seconds, the pool temperature will be displayed
again.
Note: the default temperature setting is 15°C.
5. OPERATING CONTROLS
To ensure that the heat exchanger is running correctly:
• Bring your ear close to the circulating pump, toggle the heat exchanger’s On/Off switch, if the circulating
pump is running correctly you should hear a low whistling coming from the pump motor.
• Place one hand on the inlet pipe of the primary circuit and the other on the outlet pipe of the primary
circuit, you should feel a noticeable temperature difference. A noticeable temperature difference
indicates that there is an efcient heat exchange between the primary and secondary circuits and,
therefore, that the heat exchanger is running correctly. The body of the heat exchanger should be cold
or at most at the same temperature as the pool.
• After a prolonged shut-down (winterizing), the circulating pump may fail to start up. To release it, unscrew
the central unscrew the central stud using a screw driver, rotate the shaft one way and then the other.
Once the circulating pump starts up, replace the central stud.
If, despite performing the checks listed above, the heat exchanger continues to malfunction this could be
due to:
• Incorrect sizing of the primary circuit (pressure drop too high).
• Insufcient air purge of the primary circuit.
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• Malfunction of the boiler’s main thermostat (the water in the primary circuit is not hot enough).
• Under sizing of the boiler.
«PI» is displayed continuously on the screen, and the heat exchanger does not run: check the sensor
connections or replace the sensor.
6. WINTERIZING
• Cut the power supply to the heat exchanger accessories (circulating pump, thermostat, etc.)
• Prepare the ltration group for winterizing by draining the various lines.
• Carefully drain the secondary circuit lines, especially if the secondary circuit runs outside between the
heat exchanger and the lter.
• Drain the heat exchanger body (using the drain valve on the installation or by loosening one of the
unions.
TABLE OF CODES
Kw Code Description
25 9200200 Heat exchanger BWT ET-NU 25 kW
40 9200400 Heat exchanger BWT ET-NU 40 kW
60 9200600 Heat exchanger BWT ET-NU 60 kW
90 9200900 Heat exchanger BWT ET-NU 90 kW
25 9202200 Heat exchanger BWT ET-CA 25 kW
40 9202400 Heat exchanger BWT ET-CA 40 kW
60 9202600 Heat exchanger BWT ET-CA 60 kW
90 9202900 Heat exchanger BWT ET-CA 90 kW
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7. TECHNICAL DATA
Head loss (mWC)
Primary circuit flow rate (m3/h)
Head loss on the secondary circuit (POOL)
Head loss (mWC)
Secondary circuit flow rate (m3/h)
Head loss on the primary circuit (BOILER)
25 and 40 kW
60 kW
25 kW
40 kW
60 kW
90 kW
90 kW
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- Heat exchanger BWT 25 kW -
Power output as a function of the boiler and pool water
temperatures
Temperature BOILER (°C)
Power (in kW)
pool water at 10°C
pool water at 20°C
pool water at 30°C
- Heat exchanger BWT 40 kW -
Power output as a function of the boiler and pool water
temperatures
Temperature BOILER (°C)
Power (in kW)
pool water at 10°C
pool water at 20°C
pool water at 30°C
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- Heat exchanger BWT 60 kW -
Power output as a function of the boiler and pool water
temperatures
Temperature BOILER (°C)
Power (in kW)
pool water at 10°C
pool water at 20°C
pool water at 30°C
- Heat exchanger BWT 90 kW -
Power output as a function of the boiler and pool water
temperatures
Temperature BOILER (°C)
Power (in kW)
pool water at 10°C
pool water at 20°C
pool water at 30°C
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8. FOOT PRINT OF THE HEAT EXCHANGER
25 kW and 40 kW models
60 kW and 90 kW models
176.6
176.6
30
65
30
85
30
196.1 196.1
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9. FOOTPRINT OF THE PRESASSEMBLED HEAT EXCHANGER
25 kW and 40 kW models
m60 kW and 90 kW models
131.7
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Notes
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Notes
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