Duratech SWIMMING POOL HEAT PUMP UNITS Service manual

Rev. 2.00
18.11.2009
SWIMMING POOL HEAT PUMP UNITS
Installation & Instruction Manual
DURATECH 

- series

DURATECH heat pumps
2
Contents
SWIMMING POOL HEAT PUMP UNITS ______________________________________________1
Contents__________________________________________________________________________2
1. Preface _________________________________________________________________________3
2. Specifications____________________________________________________________________4
2.1 Technical data sheet ________________________________________________________________________ 4
2.2 Dimensions _______________________________________________________________________________ 5
3. Installation and connection ________________________________________________________6
3.1 Remarks _________________________________________________________________________________ 6
3.2 Location of the heat pump____________________________________________________________________ 6
3.3 Distance from the pool ______________________________________________________________________ 7
3.4 Installation of the check-valve ________________________________________________________________ 7
3.5 Typical setup ______________________________________________________________________________ 8
3.6 Adjusting the by-pass _______________________________________________________________________ 8
4. Use and operation _______________________________________________________________11
4.1 Features of the LED control panel ____________________________________________________________ 11
4.2 Setting the parameters ______________________________________________________________________ 11
4.3 Checking the status ________________________________________________________________________ 13
4.4 Setting the CLOCK ________________________________________________________________________ 13
5. Protection systems _______________________________________________________________14
5.1 Water pressure switch ______________________________________________________________________ 14
5.2 Refrigerant gas high and low pressure protection _________________________________________________ 14
5.3 Overheating protection on the compressor ______________________________________________________ 14
5.4 Automatic defrost control ___________________________________________________________________ 14
5.5 Temperature difference between inflowing and outflowing water ____________________________________ 14
5.6 Low temperature cut-out ____________________________________________________________________ 14
5.7 Anti-frost protection during winter ____________________________________________________________ 15
6. Directions______________________________________________________________________16
6.1 Swimming pool water chemistry______________________________________________________________ 16
6.2 Setting the flow switch _____________________________________________________________________ 16
6.3 Heat pump winterizing _____________________________________________________________________ 17
6.4 Restarting the pump after winter ______________________________________________________________ 17
6.5 Check-up ________________________________________________________________________________ 17
7. Maintenance and inspection_______________________________________________________18
7.1 Maintenance _____________________________________________________________________________ 18
7.2 Troubleshooting guide______________________________________________________________________ 18
7.3 Overview of possible error codes displayed on the screen __________________________________________ 21
7.4 Check list for installation ___________________________________________________________________ 22
8. Detailed specifications ___________________________________________________________23
8.1 Electrical diagrams ________________________________________________________________________ 23
8.2 Refrigeration diagram ______________________________________________________________________ 27
8.3 Exploded views ___________________________________________________________________________ 27
9. Warranty and RMA (return material authorization)____________________________________35
9.1 Warranty ________________________________________________________________________________ 35
9.2 RMA Request Form _______________________________________________________________________ 36

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1. Preface
In order to provide our customers with quality, reliability and versatility, this product has been made according
to strict production standards. This manual includes all necessary information about installation, start-up,
winterizing and maintenance. Please read this manual carefully before opening or servicing the unit. The unit
must be installed by qualified personnel. The following conditions apply for the warranty to be valid:
•The heat pump can only be opened and serviced by a qualified installer.
•Operation and maintenance must be carried out according to the recommendations featured in this
instruction manual.
•Use genuine standard spare parts only.
Failure to comply with these recommendations will invalidate the warranty.
The company will not be held responsible for damage or injury caused by improper installation or incorrect or
unnecessary maintenance.
The Swimming Pool Heat Pump Unit heats the swimming pool water and keeps the temperature constant.
Our DURATECH

heat pumps have the following characteristics:
1. Durability
The heat pump is equipped with a PVC & Duranium heat exchanger, which can withstand prolonged
exposure to swimming pool water.
2. Easy installation
Before leaving our factory, all our heat pumps are thoroughly tested and made ready-to-use.
Only the water inlets and outlets and the electrical hook-up need to be taken care of when installing the
unit.
3. Silent operation
An extremely efficient rotary/scroll compressor and a low-noise fan guarantee silent operation of our
heat pumps.
4. Advanced controlling
By means of the electronic control panel, all parameters can be set and the status of all measured
variables can be displayed. Remote controlling can also be achieved.

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2. Specifications
2.1 Technical data sheet
Unit Model DURA-7 DURA-10 DURA-13 DURA-18 DURA-22 DURA-22T DURA-26T
kW 7 10 13 18 22 22 26
Heating capacity A25/W25 BTU/h 24000 34000 44500 61500 75000 75000 89000
kW 6,4 9,1 11,8 16,5 20,2 20,2 24,2
Heating capacity A15/W25 BTU/h 22000 31000 40500 56500 69000 69000 83000
Power input kW 1.3 1.82 2.36 3.3 4.1 4.1 4.18
Maximum power input kW 1,45 2,02 2,63 3,6 4,45 4,45 5,2
Efficiency A25/W25 C.O.P. 5.5 5.5 5.5 5.5 5.5 5.5 5.5
Maximum volume m3 30 40 60 80 90 90 120
Nominal current A 6.6 9.2 12.1 16.5 20.9 7.1 8.9
Maximum current A 6.6 9.3 13.4 18.7 21 7.9 9.5
Peak current A 24 35 45 61.5 75.5 35.8 43.2
Power supply V/Ph/Hz 220-240/1/50 220-240/1/50 220-240/1/50 220-240/1/50 220-240/1/50 3 8 0 / 3 / 5 0 3 8 0 / 3 / 5 0
Number of compressors 1 1 1 1 1 1 1
Compressor type Rotary Rotary Rotary Scroll Scroll Scroll Scroll
Refrigerant R407C R407C R407C R407C R407C R407C R407C
Amount of refrigerant Kg 0.9 1.2 1.9 2.0 2.2 2.2 2.4
Pressure gauge Yes Yes Yes Yes Yes Yes Yes
Number of fans 1 1 1 1 1 1 1
Fan power W 25 30 60 200 200 200 200
Rotational frequency of the fan RPM 950/750 950/750 950/750 830/680 830/680 830/680 830/680
Air flow m3/h 1800/1650 2100/1800 2300/2000 3200/2700 4500/3800 4500/3800 4500/3800
Fan direction Horizontal Horizontal Horizontal Vertical Vertical Vertical Vertical
Noise dB (A) 54 54 54 55 57 57 57
Water Connection mm 50 50 50 50 50 50 50
Nominal water flow m3/h 3-5 5-7 6-8 8-10 10-12 10-12 11-13
Max. water pressure drop kPa 12 15 15 16 16 16 16
Net dimensions (L/W/H) mm 950/360/580 1010/370/615 1130/470/680 660/660/860 660/660/960 660/660/960 660/660/960
Shipping dimensions (L/W/H) mm 1060/380/600 1140/400/680 1180/485/780 700/740/1010 700/740/1110 700/740/1110 700/740/1110
Net weight / Shipping weight kg 54/57 63/67 99/104 108/120 111/123 111/123 112/125
Measuring conditions: Outdoor air temp: 25°C , Inflowing water temp: 25°C, rel. humidity: 65%

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2.2 Dimensions
Model A(mm)
B(mm)
C(mm)
D(mm)
E(mm)
F(mm)
DURA-7 360 950 550
DURA-10 370 1010 615
DURA-13 470 1130 680
DURA-18 660 660 860
DURA-22 660 660 960
DURA-22T 660 660 960
DURA-26T 660 660 960
A
B
C
D
E
F

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3. Installation and connection
3.1 Remarks
The factory only provides the heat pump unit; the other parts, including a contingent by-pass, are to be provided
by the user or the installer.
Attention:
Please take the following steps when installing the heat pump:
1. Each addition of chemicals has to be performed through the conduits located downstream of the heat
pump.
2. Install a by-pass when the flow of the pool pump exceeds the authorized flow through the heat
exchanger of the heat pump with 20%.
3. Install the heat pump above the pool’s water level.
4. Always place the heat pump on a solid base and use the supplied silent blocks in order to avoid
vibrations and noise.
5. Always keep the heat pump in upright position. If the unit has been tilted, you should wait for at least
24 hours before turning it on.
3.2 Location of the heat pump
The unit will perform well on any location provided three factors are present:
1. Fresh air - 2. Electricity - 3. Pool filter piping
The unit may be installed virtually anywhere outdoors providing minimum distance requirements are met with
respect to other objects (see diagram below). For indoor pools please consult your installer. If the unit is placed
in a windy area, no problems occur with e.g. the pilot light, as opposed to what is often the case with gas
heaters.
ATTENTION: Do not place the unit in an enclosed area with a limited air volume where the unit's discharged
air will be re-circulated or near shrubs that could block the air inlet. These locations deny the unit a continuous
fresh air supply, which reduces its efficiency and may prevent adequate heat yield.
See diagram below for minimum required distances.

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3.3 Distance from the pool
Normally, the pool heat pump is installed within a 7.5 meter radius of the pool. The greater the distance from
the pool, the greater the heat loss from the piping. Since the piping is buried for the most part, heat loss is
minimal for distances of up to 30 meters (15 meters to and from the pump = 30 meters total), unless the soil is
wet or the water level is high. Heat loss per 30 meters could roughly be estimated at 0.6 kW-hour (2000 BTU)
for every 5 °C temperature difference between the pool water and the soil surrounding the pipe, which translates
to an operation time increase of 3 to 5 %.
3.4 Installation of the check-valve
Attention – When using automatic chlorine and pH dosage systems, it is of uttermost importance to protect the
heat pump from high concentrations of these chemicals that could corrode the heat exchanger. Therefore, such
systems should add the chemicals in the conduits located DOWNSTREAM of the heat pump and it is
recommended to install a check-valve in order to prevent backflow when there is no water circulation.
Damage to the heat pump caused by disregarding any of these recommendations will invalidate the warranty.

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3.5 Typical setup
Note – This setup is just an example
3.6 Adjusting the by-pass
Optimum heat pump operation is reached when the refrigerant gas reaches a pressure of 20 +/- 2 bar.
This pressure can be read from the pressure gauge located next to the control panel of the heat pump. The
adjustment also makes sure that optimum water flow is reached in the unit.
Note – The absence of a by-pass or performing an inadequate by-pass adjustment may cause the heat
pump to function less well or may even damage it, which will invalidate the warranty.
Uit In
Heat pump
F
R
O
M
P
O
O
L
T
O
P
O
O
L
Adjust the by-pass as follows:
•open the 3 valves completely
•slightly close valve 1 until
water pressure has increased
with approximately 100 to
200 grams (see also 3.8)
•close valve 3 about halfway to
adjust the pressure of the
refrigerant gas in the unit.

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3.7 Electrical hook-up
Important - Although the heat pump is electrically isolated from the rest of the unit, this only prevents
the passage of electricity to or from the pool water. Grounding the unit is still required to protect yourself
from short circuits inside the unit. Make for adequate ground connection.
Check if the electrical mains voltage corresponds with the operating voltage of the heat pump prior to hooking
up the unit.
It is recommended to use a separate fuse (slow type – D-curve) as well as adequate wiring (see table below).
For horizontal models (DURA-7/10/13/18): remove the panel on the right of the fan opening.
For vertical models (DURA-22/22T/26T): remove the corner panel with the electronic controls.
Connect the electrical wires with the terminal block labelled ‘TO POWER SUPPLY’.
Next to this connection, there is a second terminal block labelled ‘TO PUMP’, to which the filter pump (max.
5A/240V) can be connected. This connection makes it possible to control filter pump operation with the heat
pump. See further under paragraph 4.2 (parameter 9) for the different possibilities.
Remark – For models with 3 phases, switching 2 phases may cause an inversion in the rotational direction of
electrical motors, which could damage the unit. Therefore, a protection device has been built in, which will
interrupt the circuit if the connection has not been performed correctly. If you see a red LED light up at the top
of this protection device, 2 phase wires have to be switched.
Model Voltage (volt) Fuse (A) Nominal current (A) Cable diameter (mm
2
)
(for a max. length of 15
meters)
DURA-7 220-240 16 6.6 2*2.5 + 2.5
DURA-10 220-240 16 9.2 2*2,5 + 2.5
DURA-13 220-240 20 12.1 2*2.5 + 2.5
DURA-18 220-240 25 16.5 2*4 + 4
DURA-22 220-240 32 20.9 2*4 + 4
DURA-22T 3x 380 20 7.9 4*2.5 + 2.5
DURA-26T 3x 380 20 8.9 4*2.5 + 2.5

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3.8 First time start-up
Note - In order for the unit to heat the pool (or spa), the filter pump must be running so that the water
can circulate through the heat pump. Without this circulation, the heat pump will not start.
When all connections have been made and checked, you should follow these steps:
1. Turn on the filter pump. Check for leaks and verify flow to and from the pool.
2. Turn on the electrical power supply to the unit, then press the ON/OFF key “ ” on the electronic control
panel. The unit should start when the time delay period has lapsed (see further).
3. When the unit has been running for a couple of minutes, check if the air leaving the unit is cooler.
4. Check the performance of the flow switch as follows: with the unit running, turn the filter pump off. The
unit should also switch off automatically. If not, the flow switch must be readjusted. (see further under 6.2).
5. Allow the unit and filter pump to run 24 hours a day until the desired pool water temperature is reached.
When the set temperature is reached, the unit switches itself off. The unit will now automatically restart (as
long as your filter pump is running) when the temperature of the pool water experiences a drop of more than
1 °C below the set temperature.
Depending on the starting temperature of the pool water and the air temperature, it can take several days for the
water to reach the desired temperature. Covering the pool can drastically reduce this period.
Water flow switch – the unit is equipped with a flow switch that is switched on when enough water has flowed
through the unit and that is switched off when the water flow becomes too low (e.g. when the filter pump is
switched off). If the pool water level is located more than one meter above or below the heat pump, your
installer may need to adjust this flow switch (see further under 6.2).
Time delay – the unit is equipped with a built-in 3-minute start delay included to protect electrical components
and contacts. After this time delay, the unit will automatically be restarted. Even a brief interruption of the
power supply will activate the start delay and prevent the unit from starting immediately. Additional
interruptions of the power supply during the delay period will have no effect on the 3-minute countdown.
3.9 Condensation
When the swimming pool water is being heated by the heat pump, the incoming air is cooled down quite a bit,
which can cause condensation on the fins of the evaporator. Condensed volumes can attain several litres per
hour under high atmospheric humidity. Sometimes, this is wrongfully interpreted as a water leak.

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4. Use and operation
4.1 Features of the LED control panel
With the “On/Off” key “ “, the heat pump is turned on or turned off (stand-by status). If the LED next to this
key lights up, the heat pump is turned ON.
Setting the desired temperature of the swimming pool water is achieved with the arrow keys, regardless if the
heat pump is turned ON or OFF. You simply press the arrow keys to set the desired temperature directly.
•When the unit is turned ON and is running, the temperature of the swimming pool water can be read off the
LED screen.
•When the unit is turned ON and the desired temperature is reached, “OFF” appears on the LED screen.
•When the unit is turned OFF, “OFF” is always displayed on the LED screen; the heat pump goes on
monitoring all parameters of the system and all protection systems remain active. The heat pump is thus in
STAND-BY mode. We will continue using this expression if we wish to indicate that the heat pump is
turned OFF.
4.2 Setting the parameters
Parameters can always be checked by pressing the service key “ ”, regardless if the pump is turned ON or is in
STAND-BY mode. Only in STAND-BY mode can the parameters be modified.
This is an overview of the different parameters and their standard values.
Press “ ▲” or “▼” to modify
settings
On/Off Press “CLOCK” to set the
time
LED screen
Access to parameters

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The first number on the LED screen stands for the number of the parameter and the second one for its value.
Parameter
Description Standard
0 Desired temperature in cooling mode (6
⇒ 28°C) 20°C
1 Desired temperature in heating mode (6
⇒ 40°C) 27°C
2 Operation time of the compressor before defrosting mode starts (30
⇒ 90 minutes) 45 min
3 Temperature of evaporator at which defrosting starts (-30
⇒ 0°C) -7°C
4 Temperature of evaporator at which defrosting stops (2
⇒ 30°C) 13°C
5 Maximum duration of defrosting procedure (0
⇒ 12 min) 8 min
6 Mode of electronic expansion valve (0 for ‘MAN’ and 1 for ‘AUTO’) 1
7 Memory function for automatic start-up (0 for ‘NO’ and 1 for ‘YES’) 1
8 Operating mode –heating only 3
9 Not used
10 Not used
11 Target Superheat 3
12 Manual Control for EE valve (15
⇒ 47 steps) 35
13 Temp. of inflowing water
14 Temp. of outflowing water
15 Temp. of evaporator
16 Return gas temp.
17 Ambient temp.
18 Temp. of exhaust gas
19 Actual open steps of EE valve
Parameters 2 up to and including 5 are the settings for the automatic defrosting mode. They have been set
from the factory for optimal operation and very rarely need to be adjusted by a specialized technician, that is,
only if conditions demand it.
Parameter 6 indicates the mode of the electronic expansion valve. When put in AUTO mode ‘1’ the valve is
controlled by temperature. If put in MAN mode ‘0’ the valve is controlled by the stepping motor, which can be
controlled by parameter 12.

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Parameter 7 indicates if the heat pump should or shouldn’t start automatically after an interruption of the
power supply.
Parameter 11 controls the opening/closing of the expansion valve. This can be controlled from –20 to 20°C and
has a standard value of 3°C.
Parameters are modified as follows:
•Set the heat pump in its STAND-BY mode.
•Press the service key “ ” to access the parameter menu. The parameter number and its value will blink
simultaneously.
•Press the arrow key “ ▲” or “▼ ” to select the desired parameter.
•Then press “MODE” and “ ” simultaneously. Now, only the value of the parameter will be blinking.
•Then select the desired setting with the arrow key “ ▲” or “▼ ”.
•Stop for 5 seconds or press the service key to save the new setting. The LED screen will again display
“OFF”.
Only parameters 0 and 1 (depending on the selected mode) are set directly with “▲”or“▼”
4.3 Checking the status
Further down in the parameter menu, after numbers from 0 to 12, you encounter parameters 13 to 19.
These cannot be modified. They indicate the values the unit is currently measuring for these parameters.
Parameter Measured value
13 Temperature of inflowing water
14 Temperature of outflowing water
15 Temperature of evaporator
16 Temperature of returning gas
17 Ambient temperature
18 Temperature of exhaust gas
19 Position stepper motor
4.4 Setting the CLOCK
•Start setting the clock by pressing the “CLOCK” key. The LED screen will display the time and the hours
will start to blink.
•Press “ ▲” or “▼ ” to set the desired hour.
•Press “CLOCK” again. Now, the minutes start blinking.
•Press “ ▲” or “▼ ” again to set the minutes.
•Press “CLOCK” again to save the settings.

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5. Protection systems
DURATECH

heat pumps are equipped with the following standard protection systems:
5.1 Water pressure switch
Thanks to this pressure switch, the heat pump will not work when the filter pump is not working (and the water
is not circulating). This system prevents the heat pump from heating only the water present in the heat pump
itself. The protection also stops the heat pump if water circulation is cut off or stopped.
5.2 Refrigerant gas high and low pressure protection
The high pressure protection makes sure the heat pump is not damaged in case of overpressurisation of the gas.
The low pressure protection emits a signal when refrigerant is escaping from the conduits and the unit cannot be
kept running.
5.3 Overheating protection on the compressor
This protection protects the compressor from overheating.
5.4 Automatic defrost control
When the air is very humid and cold, ice can form on the evaporator. In that event, a thin layer of ice appears
that will grow increasingly bigger as long as the heat pump is running. When the temperature of the evaporator
has become too low, automatic defrost control will be activated, which will reverse the heat pump cycle so that
hot refrigerant gas is sent through the evaporator during a brief period of time to defrost it.
5.5 Temperature difference between inflowing and outflowing water
During normal operation of the heat pump, the temperature difference between inflowing and outflowing water
will approximate 1 to 2 °C. In the event that the pressure switch does not work and that the water stops
circulating, the temperature probe monitoring the outflowing water will always detect a rise in temperature. As
soon as the temperature difference between inflowing and outflowing water exceeds 13 °C, the heat pump will
be automatically turned off.
5.6 Low temperature cut-out
If, during cooling, the temperature of the outflowing water reaches 5 °C or drops below this temperature, the
heat pump will turn itself off until the water temperature reaches or exceeds 7 °C again.

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5.7 Anti-frost protection during winter
This protection can only be activated if the heat pump is in STAND-BY mode.
5.7.1 First anti-frost protection
If the filter pump is controlled by the heat pump (regardless of the value for parameter 9) and when the water
temperature lies between 2 and 4 °C and the air temperature is lower than 0 °C, the filter pump will be
automatically turned on to prevent the water from freezing in the piping. This protection is deactivated when the
temperature rises again.
5.7.2 Second anti-frost protection
If the water temperature drops even more, that is, below 2 °C (during long frost periods), the heat pump will
also start running to heat the water until its temperature approximates 3 °C. When this temperature is reached,
the heat pump will stop, but anti-frost protection will remain active until conditions change.

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6. Directions
6.1 Swimming pool water chemistry
Special attention should be paid to the chemical balance of the pool water. The pool water values should always
stay within the following limits:
Min. Max.
pH 7.0 7.8
Free chlorine (mg/l) 0.5 1.2
TAC (mg/l) 80 150
Salt (g/l) 8
Important: failure to comply with these limits will invalidate the warranty.
Note: exceeding one or several limits can damage the heat pump beyond repair. Always install water
treatment equipment past the heat pump’s water outlet, especially if the chemicals are automatically
added to the water.
A check-valve should also be installed between the outlet of the heat pump and this equipment in order to
prevent products from flowing back into the heat pump if the filter pump stops.
6.2 Setting the flow switch
The water flow switch is set to 0.14 bar by default. As from this water pressure value, the heat pump will be
able to function. This is the minimum required water pressure for most installations.
This setting may only be modified if the heat pump does not start running despite sufficient water circulation or
if it does not stop when the filter pump stops.
Always make sure that the water filter is clean before adjusting the settings of the flow switch: a dirty filter will
lower the water flow and hamper correct adjustment of the flow switch settings.
Directions:
1. Check that all valves are opened so that water can run through the heat pump. Start the filter pump.
2. Start the heat pump.
3. If the heat pump does not start after the time delay, there might not be enough water circulation. Investigate
and correct contingent circulation problems prior to adjusting the flow switch.
4. Remove the heat pump’s access panel. The flow switch is located on the lower right.
5. Turn the screw on the flow switch slowly in anticlockwise direction. Wait for the time delay.
6. Repeat step 5 until the heat pump starts running.
7. Once the heat pump is running, stop the filter pump. The heat pump should immediately turn itself off.
8. If the heat pump does not turn itself off, the screw should be turned clockwise until the heat pump stops.
9. Check once more if the flow switch functions correctly by turning the filter pump on and off.

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6.3 Heat pump winterizing
Important: failure to take the necessary precautions for winterizing can damage the heat pump, which
will invalidate the warranty.
The heat pump, filter pump, filter and conduits must be protected in areas where the temperature can drop below
the freezing point. Evacuate all water from the heat pump as follows:
1. interrupt the electrical power supply to the heat pump
2. close the water supply to the heat pump: completely close valves 2 and 3 of the by-pass
3. disconnect the water inlet and outlet coupler fittings of the heat pump and let the water drain out of the unit
4. loosely reattach water inlet and outlet coupler fittings to the heat pump in order to prevent dirt from getting
into the conduits.
Note: these precautions should not be taken if you choose to use the built-in anti-frost protection.
6.4 Restarting the pump after winter
If you purged your heat pump for winterizing, you should undertake the following steps to restart it in spring:
1. check first if there is no dirt in the conduits and if there are no structural problems
2. check if the water inlet and outlet coupler fittings are adequately fastened to the heat pump
3. start the filter pump to start the water flow to the heat pump. Set the by-pass again.
4. reconnect the electrical power supply to the heat pump and turn it ON.
6.5 Check-up
DURATECH

heat pumps have been developed and built to last, that is, if they have been installed correctly
and can run under normal conditions. Regular check-ups are important if you want your heat pump to function
safely and efficiently for years on end.
The following directions can help you achieve optimal results:
1. make for easy access to the service panel
2. keep the area surrounding the heat pump free of contingent organic waste
3. prune the vegetation near the heat pump so that there is enough free space around the pump
4. remove contingent water sprinklers from the vicinity of the heat pump. They can damage the heat pump.
5. prevent rain from directly running off a roof onto the heat pump. Install proper drainage.
6. do not use the heat pump if it has been flooded. Immediately contact a qualified technician to inspect the
heat pump and repair it if should prove necessary.
Condensation can occur when the heat pump is running. This condensation can flow away through an opening
in the base pan of the unit. The amount of condensation water will increase when atmospheric humidity is high.
Remove any dirt that could possibly hamper the evacuation of condensation.
10 to 20 litres of condensation water can be produced while the unit is running. If more condensation is
produced, stop the heat pump and wait for one hour before checking for leaks in the conduits.
NOTE: A quick way to verify that the water running through the condensation drain is indeed
condensation, is to shut off the unit and keep the pool pump running. If the water stops running out of the
condensation drain, it is condensation. AN EVEN QUICKER WAY is to TEST THE DRAIN WATER
FOR CHLORINE. If no chlorine is detected, the drain water is a result of condensation.
Also take care to leave air inlet and exhaust passages free. Prevent exhaust air from immediately re-entering the
unit through the inlet.

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7. Maintenance and inspection
7.1 Maintenance
•Check the water inlet and drainage often. The water and air inflow into the system should be sufficient so
that its performance and reliability does not get compromised. You should clean the pool filter regularly to
avoid damage to the unit caused by clogging of the filter.
•The area around the unit should be spacious and well ventilated. Clean the sides of the heat pump regularly
to maintain good heat exchange and to save energy.
•Check if all processes in the unit are operational and pay special attention to the operation pressure of the
refrigerant system.
•Check the power supply and cable connections regularly. Should the unit begin to function abnormally or
should you notice a smell from an electrical component, arrange for timely repair or replacement.
•Winterizing : make sure to purge all the water from the heat pump and other systems in order to prevent
frost damage.
•You should also purge the water if the unit will not work for an extended period of time. You should check
all parts of the unit thoroughly and completely fill the system with water before turning it on again
afterwards.
7.2 Troubleshooting guide
Improper installation may result in an electrical discharge that could lead to death of – or serious injury to –
pool users, installers or others due to electrical shock and may also cause damage to property.
DO NOT attempt to modify the internal configuration of the heat pump.
1. Keep your hands and hair clear of the fan blades to avoid injury.
2. If you are not familiar with your pool filtering system and heat pump:
a. Do not attempt to adjust or service without consulting your dealer or your professional pool or air
conditioning contractor.
b. Read the entire installation and user manual before attempting to use, service or adjust the unit.
c. Start the heat pump at least 24 hours after its installation in order to prevent damage to the
compressor.
Nota: Switch off the power prior to maintenance or repairs.
Important remark: if a malfunction cannot be resolved immediately, your
installer can contact our customer service. To be able to help you, we will need
the serial number of your heat pump.
In order to analyse the problem itself, we will need to know the message (error
code) that is displayed on the LED screen, as well as the values for the settings
(parameters 0 to 9) and for the status of the heat pump (parameters A to E) just
before the failure or, if this is impossible, just after it.
Please keep this information at hand when calling our customer service. This
information is also indispensable if you need to return a heat pump. Returning the
unit should occur according to our RMA procedure guidelines.
On the following pages, you will find an overview of the different types of failure problems that can occur,
along with directions to solve them.

DURATECH heat pumps
19
Problem: the heat pump doesn’t work
Observation: the screen does not light up and the fan/compressor doesn’t make a sound
Possible cause Solution
No electrical power supply Check power supply (wiring, fuses, ...)
Problem: the heat pump doesn’t work
Observation: the screen displays “OFF” and the LED next to “ ” is not lit
Possible cause Solution
The pump is in stand-by mode Turn on the pump
Problem: the heat pump doesn’t work
Observation: the screen displays “OFF” and the LED next to “ ” is lit
Possible cause Solution
1. The set temperature has been reached 1. No action required; all is well
2. The heat pump isn’t functioning yet 2. Wait until the start time delay period has lapsed (3
minutes)
Problem: the heat pump works but doesn’t heat
Observation: the compressor is running but the fan isn’t and the “HEATING/DEFROST” LED is blinking
Possible cause Solution
The defrosting cycle is running No action required; all is well
Problem: the heat pump works normally but there is no or insufficient heating
Observation: the screen displays the temperature but no error codes
Possible cause Solution
1. Insufficient capacity of the heat pump in
proportion to the size of the swimming pool
1. Install a larger sized model or an extra heat pump.
Cover the pool to limit heat loss
2. The compressor works but the fan doesn’t 2. Check the electrical wiring of the fan. Replace the
condenser or the fan motor if necessary.
3. The fan works but the compressor doesn’t 3. Check the electrical wiring of the compressor.
Replace the condenser or the compressor if
necessary.
4. The heat pump has not been placed on an optimal
location
4. Make for sufficient air circulation (see manual for
details)
5. Faulty temperature setting 5. Set the correct temperature
6. By-pass not adjusted 6. Have the by-pass readjusted by the installer
7. Massive ice formation on the evaporator 7. Have the settings for automatic defrost control
checked by the installer
8. Not enough refrigerant 8. Have the heat pump checked by a refrigeration
technician
Problem: the heat pump works normally but the water is cooling down instead of heating up
Observation: the screen displays the temperature but no error codes
Possible cause Solution
1. The wrong mode has been selected 1. Verify the parameters, select the correct mode
2. The controller is out of order 2. Check the voltage in the electrical wiring to the 4-
way valve. If no electric potential is measured,
replace the controller
3. The 4-way valve is out of order 3. Check the voltage in the electrical wiring to the 4-
way valve. If electric potential is measured,
replace the coil. If the problem persists, have the
heat pump checked by a refrigeration technician

DURATECH heat pumps
20
Problem: the heat pump works but stops after a short while
Observation: the screen displays “OFF”
Possible cause Solution
1. Wrong setting of parameters 1. Check the settings of the parameters and modify if
necessary
Problem: the heat pump doesn’t stop
Observation: the screen displays the temperature but no error codes
Possible cause Solution
1. Wrong setting of parameters 1. Check the set parameters and adjust them if
necessary (settings just above the capacity of the
heat pump)
2. Pressure switch out of order 2. Check operation of the pressure switch by turning
off the filter pump and restarting it. If the heat
pump doesn’t react to this, the pressure switch
must be adjusted or replaced.
3. Electrical failure 3. Contact your installer
Problem: water leak
Observation: there’s an amount of water under the heat pump
Possible cause Solution
1. Condensation due to atmospheric humidity 1. No action required
2. Water leak 2. Try to localize the leak and check for the presence
of chlorine in the water. If that is the case, the heat
pump must be temporarily replaced during repair.
Problem: abnormal amount of ice formed on the evaporator
Observation: the evaporator is for the most part covered in ice
Possible cause Solution
1. Insufficient air inflow 1. Check the location of the heat pump and remove
any dirt that could be present on the evaporator
2. High water temperature 2. If the pool water is already quite hot (warmer than
29 °C), the probability of ice formation increases.
Lowering the set temperature is a possible option.
3. Incorrect setting of automatic defrost control 3. Check the settings of the defrosting function
together with your installer
4. The 4-way valve is out of order 4. Check the voltage in the electrical wiring to the 4-
way valve. If electric potential is measured,
replace the coil. If the problem persists, have the
heat pump checked by a refrigeration technician.
5. Not enough refrigerant 5. Have the heat pump checked by a refrigeration
technician.