Kronoterm WP4 LF-502 Operation manual

Instructions For Use And Installation
Heat Pumps for Sanitary Water Heating
WP4 LF-502
This manual is to be handed over to the end user after installation!
ID.: 17-16-20-2979-10 / 3.2018
EN

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Instructions for use and installation - Version 10 / Released on 3.2018
Printed in Slovenia, Copyright by Kronoterm d.o.o.
This document is copyrighted. Any use outside the provisions of the copyright law without the
permission of Kronoterm d.o.o. is illegal and punishable by law. All previous versions of this
document are void. We reserve the right to make changes. We reserve the right to change
this document and for printing errors.

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1. Index
1. Index....................................................................................................................... 3
2. Important Information........................................................................................... 5
2.1 Symbols.................................................................................................................. 5
2.2 General Warnings and Instructions ......................................................................... 5
2.3 Safety Warnings and Instructions............................................................................ 6
2.4 Obligations of the Manufacturer............................................................................... 9
2.5 Obligations of the Installer....................................................................................... 9
2.6 Customer Support - Service.................................................................................... 9
2.7 Obligations of the User............................................................................................ 9
2.8 Factory Testing ......................................................................................................10
2.9 Storage ..................................................................................................................10
2.10 Transportation........................................................................................................10
2.11 Delivery Content.....................................................................................................10
3. Technical Description..........................................................................................11
3.1 General..................................................................................................................11
3.2 Components...........................................................................................................11
3.3 Operation Principle.................................................................................................13
4. Position of Connections and Dimensions..........................................................14
5. Installation............................................................................................................15
5.1 Minimal spacing of the device: ...............................................................................16
5.2 Device Levelling.....................................................................................................17
5.3 Hydraulic Connection.............................................................................................17
5.4 Air Canal Installation ..............................................................................................19
5.5 Connection of Condensation Outlet........................................................................20
5.6 Connection of External Heating Source (alternative / additional source).................21
5.7 Placement of External Controller Temperature Probe ............................................25
5.8 Parallel Connection of Several Devices..................................................................26
5.8.1 Connection of Cold - Hot Water and Circulation.....................................................26
5.8.2 Connection to Boiler...............................................................................................27
5.8.3 Air Canal Connection .............................................................................................27
5.9 Electric Connection ................................................................................................28
5.9.1 Power Supply:........................................................................................................29
5.9.2 Additional Heat Source Connection........................................................................30
6. Device Startup......................................................................................................31
6.1 Filling Device with Water........................................................................................31
6.2 Controls Before Startup..........................................................................................31
6.3 Device Startup........................................................................................................31
7. Controller..............................................................................................................32
7.1 Basic Window.........................................................................................................32
7.1.1 Sanitary Water Temperature..................................................................................32
7.1.2 System statuses.....................................................................................................32
7.1.3 Setting of Desired Temperature of Sanitary Water .................................................33
7.2 Screensavers.........................................................................................................33
7.2.1 All screensavers.....................................................................................................33
7.3 Menu......................................................................................................................34
7.3.1 Error Acknowledgement.........................................................................................35
7.3.2 Quick Water Heating..............................................................................................35
7.3.3 Basic Operation Programme..................................................................................35
7.3.4 Temperature Deviation ECO..................................................................................35
7.3.5 Temperature Deviation COMFORT........................................................................35
7.3.6 Daily Schedule.......................................................................................................35
7.3.7 Ventilation Schedule...............................................................................................36
7.3.8 Vacation.................................................................................................................37

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7.3.9 Time.......................................................................................................................37
7.3.10 Backup Source.......................................................................................................37
7.3.11 Overheating Programme - Anti-legionella...............................................................38
7.3.12 Automatic Quick Water Heating..............................................................................38
7.3.13 Screen Brightness..................................................................................................38
7.3.14 System Information ................................................................................................38
7.3.15 Advanced Installation Settings ...............................................................................39
8. Device Operation Setting.....................................................................................41
8.1 Basic Operation......................................................................................................41
8.1.1 Basic Operation Programmes ................................................................................41
8.2 Additional Source...................................................................................................42
8.2.1 Correct choice of the additional source...................................................................42
8.2.2 Choosing the correct operation mode of the external source..................................42
8.3 Additional Operation Programmes..........................................................................43
8.3.1 Backup Source.......................................................................................................43
8.3.2 Quick Water Heating..............................................................................................43
8.3.3 Anti-freeze Programme..........................................................................................44
8.3.4 PHOTOVOLTAICS.................................................................................................44
8.3.5 "Bivalent mode" Programme ..................................................................................44
8.3.6 "Defrost" Programme .............................................................................................44
9. Errors and Warnings............................................................................................45
9.1 Warnings................................................................................................................45
9.2 Errors.....................................................................................................................46
9.3 Errors of the OPTITRONIC 2 - WEB module (option):............................................48
10. Removal and Disposal.........................................................................................49
11. Maintenance and Care .........................................................................................49
12. Errors in Operation ..............................................................................................49
13. Electrical Connection Scheme............................................................................50
14. Technical data......................................................................................................51
15. Legend of data label.............................................................................................52

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2. Important Information
The manuals describe the process of installation and maintenance of the device. The
installation and maintenance can only be performed by qualified personnel. Read the manual
carefully before the installation, this way you will be informed about the intended use,
functionality and process of handling the device.
The manual has to be handed over to the end user after installation.
In case the product is given for use to a third person, the manual has to be handed
over to them as well.
Explanation of Terms
An informed person is a person who reads this manual.
A trained person has a certificate of professional training.
An authorised service technician has been trained and authorised to service and
perform maintenance on the device by the manufacturer.
The user is the one using the device for its intended purpose.
The installation technician is a professional, trained to carry out machine or electrical
installation work and the installation of the device.
Inappropriate handling of the device can cause a defect of the device, injuries to the user or
property damage. To limit risks, the manual uses symbols to emphasize important
information.
2.1 Symbols
When installing, performing maintenance or using, various levels of danger may occur. In
certain parts of these instructions, you will find warnings, with which we wish to ensure the
safety of the user, remove the potential dangers and ensure the proper operation of the
device.
These symbols mark various risks for the user or the device.
DANGER: Risk of situations which can lead to serious physical injuries.
WARNING: Risk of situations which can lead to minor physical injuries.
CAUTION: Risk of situations which can lead to damage or malfunction of
the device.
This symbol marks information for the user.
NOTE: A notice holding important information regarding requirements of the
manufacturer and the device.
2.2 General Warnings and Instructions
NOTE
Before beginning the installation read the installation and operation manual.
NOTE
Any modification or replacement of original components of the device makes
the guarantee of the manufacturer for safe and functional operation null and
void. In any case of improper use of the devise or uses it was not intended
for, the manufacturer is not liable for consequences and will reject any
claims. Injuries and damage to the device or other property due to improper

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use are the explicit responsibility of the user alone.
NOTE
Device installation must be carried out in compliance with instructions or the
warranty is null and void.
NOTE
When designing, projecting, installing and using the device, it is obligatory to
take all technical data, warnings and notes from this manual into
consideration.
DANGER
Failure to follow instructions and good practices when performing the
electrical connection of the device may cause severe injuries and death.
WARNING
This device is intended for use in houses. Use of the device in hotels, stores,
farms, light industry and other public buildings is permitted to experts or
properly trained personnel.
WARNING
Electrical connection of the device may only be carried out by a trained
installation technician for electric installations.
2.3 Safety Warnings and Instructions
WARNING
The device must not be placed where there are harmful substances, which
could damage it, in the air (barns, dangerous substance storage, open air,
etc.).
WARNING
The inflow pipe must obligatorily be equipped with a safety valve with
nominal pressure of 0.6 MPa (6 bar), which prevents pressure increase in
the water heater above the nominal pressure.
WARNING
Transportation of the device is only permitted in upright position.
WARNING
The water heater is intended for potable water storage, so it must obligatorily
comply with valid national regulations on potable water, or the device could
get damaged and the validity of warranty nullified.
WARNING
The device must never operate without water in the hot water tank.
WARNING
The electrical connection of the power supply cable must be carried out by a
qualified electrician.

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WARNING
Connection of the device to the power grid must take place in accordance with
standards for connection to electrical grids. The device must be connected to the
electrical grid via a shutdown element, built into the electrical installation according
to valid regulations. The shutdown element must separate all contacts under the
conditions of overload category III.
WARNING
Water from the device is drained through the inflow pipe of the water heater.
For this purpose, it is recommended to add a special link or release valve
between the safety valve and the inflow pipe.
WARNING
To ensure proper operation of the safety valve, carry out regular annual
controls of valve operation. If required, clean limescale and make sure that
the safety valve is not blocked.
WARNING
Water may drip from the release pipe of the overflow. The pipe must be
exposed to outside air. Should you add a valve to the pipe, it has to be
turned downwards, so that the water in it cannot freeze.
WARNING
It is forbidden to play with the device. Children are strictly forbidden from
cleaning the device without supervision.
WARNING
The device may be independently used only by person, familiar with the safe
operation and understanding possible dangers of the device. Children above
8 years of age and persons with reduced physical and mental abilities, or
with the lack of experience and knowledge, may only used the device under
supervision of an instructed person.
WARNING
During operation, it is forbidden to move, shift, clean or repair the device.
WARNING
Cleaning and maintenance of the device is forbidden to unsupervised
children.
WARNING
Before installation and any later intervention in the device, always comply
with instructions for safe use and maintenance.
WARNING
Installation must be carried out in compliance with the valid regulations and
according to the instructions of the manufacturer, by a professionally trained
person.

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WARNING
The device must not be stacked or have items lean against it. If, while the device is
operational, the water temperature exceeds 80 °C, contact service.
WARNING
Ensure, that the device does not represent a danger to anyone. Access to
device must be prevented to children and uninstructed persons.
WARNING
Do not place the device into a room where it could not be removed from.
Later building around it or placement of other obstructions by the device is
forbidden.
WARNING
Service and maintenance of the device may only be carried out by a service
technician, authorised by the manufacturer. In case of a defect, first contact
the installation technician that installed the device.
WARNING
Never clean the device with cleaning agents which contain sand, soda, acid
or chlorides, as they can damage the surface of the device.
WARNING
The device contains the coolant R134a, which, compliant with the Kyoto
Protocol, is listed among greenhouse gasses. Thus work on the device is
only permitted to authorised persons for handling of coolant as defined by
the law in force. During interventions into the device, escape of coolant into
the atmosphere must be prevented.
WARNING
In avoidance of dangers, a damaged power cable may only be replaced by
the manufacturer or an authorised installation technician..

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2.4 Obligations of the Manufacturer
The manufacturer guarantees that the device is compliant with valid European directives and
standards. The device is marked with the CE mark and has all required documentation.
We reserve the right to change instructions without previous notifications.
The manufacturer accepts no liability in the case of:
Failure to follow device installation instructions.
Failure to follow device use instructions.
Wrong or inadequate device maintenance.
2.5 Obligations of the Installer
The installer is responsible for the installation and start-up of the device in accordance with
the following:
Read instructions for installation and use which come with the device thoroughly
before installation.
The device must be installed in compliance with the valid national legislation,
directives and standards.
First start-up must be carried out and potential initially present defects removed upon
detection.
The user must be trained to use the device and the settings.
The user must be warned to regularly perform maintenance on the device to ensure
proper operation during the entire operational life of the device.
Operation of the entire system must be explained to the user.
The user must be given all documentation that came with the device.
2.6 Customer Support - Service
Customer support and service while warranty lasts are provided by device manufacturer.
When submitting a service claim, we ask you to provide the following information:
Exact name of the product.
Serial number.
Year of manufacture.
All required data is listed on the label on the device.
NOTE
In any case of a change or replacement of original components, forced or improper
use of the device, the warranty becomes null and void. Possible expenses
stemming from a service intervention are charged to the user in their entirety.
During warranty period, only the manufacturer or a service, authorised by the
manufacturer, may carry out service and maintenance procedures. If that is not the
case, the warranty becomes null and void.
2.7 Obligations of the User
To ensure uninhibited and efficient operation of the device, the user must take into
consideration the following instructions:
Read instructions for installation and use which come with the device thoroughly.
Installation and start-up of the device must be carried out by a trained and authorised
professional.
Allow the authorised installer or ask them to thoroughly explain the functioning and
means of operation of your device.
You must ensure regular check ups and maintenance of the device by an authorised
service technician.
Keep instructions for installation and use in a suitably dry place, close to the device.

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2.8 Factory Testing
To ensure a high quality standard, all heat pumps are tested before leaving the factory in the
following aspects:
Sealing tightness of the cooling circuit.
Watertightness.
Airtightness.
Electric safety.
Functionality.
2.9 Storage
The device must be stored in a dry and clean area. Allowed storage temperature is between
10 and 45 °C, short term (up to 24 hours) also up to 55 °C.
2.10 Transportation
Before transportation, the device has to be protected with a protective foil or cardboard
packaging, in order to prevent mechanical damage.
WARNING
When moving the device, it is obligatory to unplug it from the power grid.
WARNING
The device has impact sensitive parts so it is important to avoid any impacts
during transportation or any instance of the pump falling.
WARNING
The mass of the device exceeds the permitted lifting mass for one person. All
liability for possible personal injury, property or device damage is borne by the
client.
WARNING
It is forbidden to place the device in a horizontal position.
2.11 Delivery Content
Delivery Content:
1. Heat pump
2. Water condensation removal pipe
3. Instructions for use and installation

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3. Technical Description
3.1 General
This device is a heat pump for the heating of sanitary water in residential areas and small
business premises. When heating sanitary water, the heat pump also cools the area, from
which air is captured and / or returned to. The heat pump can thus along with heating of
sanitary water, be used for cooling of indoor areas, whereby it has to be emphasized, that
the heat pump will only cool the area, if there is a need to heat the sanitary water.
NOTE
For the highest efficiency and savings, we recommend that you use air from areas
with waste heat (boiler room, laundry room, kitchen, cellar, pantry) as a heat
source and that the air temperature is as high as possible.
3.2 Components
A
A
Device generator casing
B
Fan
C
Evaporator
D
Compressor
E
Dehydrator
F
Thermoekspansion valve
G
Controller
H
Hot sanitary water tank
(boiler)
I
Heat exchanger (heating
water)
J
Anti-corrosion anode
K
Condenser
L
Electric heater
M
Connection for additional
electric heater
C
D
E
B
F
J
G
H
J
L
K
I
M

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The device consists from the device generator (compressor, evaporator, fan, ...) and the hot
water tank. The housing of the generator is made of durable plastic and is heat and sound
isolated. The device has two attachments for air channels which enable a remote air intake
and exhaust from neighbouring rooms or the environment. The hot sanitary water tank is
equipped with a piped heat exchanger, which can be connected to an external fossil fuel,
biomass or solar energy collector powered boiler.
Hot Sanitary Water Tank
Sanitary water heater is enamelled with patented technology, heat isolated with polyurethane
and mechanically protected with sheet metal. The tank is serially equipped with a water heat
exchanger that can be connected with a boiler when choosing an additional heat source. An
Mg anode is also placed into the tank, preventing corrosion of the heater upon potential
mechanical damage to the enamel.
Electric Heater
The device is serially equipped with two electric heaters with a power of 2 x 2 kW, which
serves as an additional or backup heating source.
Along with both already installed heaters, it is possible to install an additional heater into the
hot sanitary water tank with a 6/4" attachment with separate power supply.
Anti-freeze probe
Regulator of heat pump senses the temperature of the vaporizer. In the case, that the
temperature of the vaporizer is below -7 °C, it will perform a safety shutdown of the device for
at least 30 minutes. In such a case, the heat pumps with an electric heater automatically
switch to electric heating and the heat pumps with an attached boiler switch to boiler heating
(circulation pump switch on).
Safety thermostat
The electric heater contains a safety thermostat with a limit at 85 °C. This means that, in the
case that the temperature in hot water tank is exceeded, the power supply will be switched
off and the device will stop operating. To restart the device, call authorised installation
technician who must verify and remove the reason of the safety shutdown of the device.
WARNING
When heating with boiler or solar collectors, you may heat the water in the hot
water tank to a temperature above 80 °C whereby the safety thermostat switches
off. In such a case the thermostat has to be manually reset. To restart the
thermostat, an authorised installation technician must be called.
Boiler water temperature control
Monitoring and heating of water to desired temperature is ensured by the advanced
OPTITRONIC 2 touchscreen regulator.
In regards to the set up desired water heating temperature, the controller, as required,
switches the compressor and fan on or off, and, under certain conditions, also switches the
electric heater or circulation pump of the boiler on or off. The maximal temperature of water
heating that can be set up is 65 °C. Should the temperature in hot water tank increase over
75 °C, the controller switches off all sources of heat for safety reasons.
Minimal temperature of water in hot water tank is 7 °C.
High pressure cooling system protection
To prevent pressure in the cooling system to get too high and potential damage, related to it,
a high pressure safety switch is installed, which stops the operation of the heat pump in the
case of pressure rising beyond a preset point.
Conditions of operation
Environment temperature must be between -7 °C and +35 °C. The air must be clean with
relative humidity not exceeding 50% at +35 °C. At lower air temperatures, the relative air

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humidity may be higher. Devices, placed at higher altitudes above sea level may function
less efficiently due to lower air pressure.
3.3 Operation Principle
56
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10
1
2
9
1. Compressor
6. Fan
2. Condenser
7. Magnetic valve
3. Dehydrator
8. Temperature bulb of the expansion valve
4. Thermoexpansion valve
9. Electric heater
5. Evaporator
10. Hot sanitary water tank (boiler)
The cooling system of the heat pump is a closed circuit system, within which the coolant R134a
circles as a heat exchanger. At lower pressure and lower temperature (e.g. 10°C), the coolant is
vaporised in the heat pump vaporizer, thereby drawing heat from the air. Then, the coolant is
compressed to a higher pressure in the compressor, which makes its temperature rise to the
temperature, higher than that of the water in the boiler. The coolant then gives away the heat to
the water in the condenser, whereby it liquefies. The expansion of the coolant, which makes the
coolant pressure and temperature lower to the primary value, the circular process is concluded.
This process is repeated throughout the heat pump operation time.

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4. Position of Connections and Dimensions
A
Connection cold water G1''
B
Connection heat exchanger –return pipe G1''
C
Connection heat exchanger –supply pipe G1''
D
Circulation connection G3/4''
E
Hot water connection G1''
F
Connection for removal of water condensation 16
G
Connection for additional electric heater 6/4''
H
Connection for the installation of a watertight tube with a threaded plug G1/2’’ for
the measurement of cold water temperature.
I
Channel for the temperature sensor of the heat exchanger

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5. Installation
The lowest height of ceiling in the room must be 2500. The device is made so that it takes
heat from surrounding air or sucks it through air channels and blows it into neighbouring
rooms or the environment. The device may be installed in the following ways.
Figure 1: Suction and exhaust in the same room (e.g. pantry cooling).
Figure 2: Suction of the outside air, exhaust into the surroundings
.
Figure 3: Suction and exhaust into neighbouring room (e.g. pantry cooling).
The most common placement of the heat pump is such, that the air is sucked from areas,
where there is a lot of waste heat. This air has a part of its heat removed, then released into
the surrounding. Air in kitchens, laundry rooms, sanitary facilities often contains unpleasant
odours, so it is blown into the environment. Thereby we must be careful that the air flows and
pressures in spaces are evened out, which must be ensured by the projecting engineer for
the ventilation.

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WARNING
The device must not be placed where there are harmful substances, which
could damage it, in the air (barns, dangerous substance storage, open air,
etc.).
5.1 Minimal spacing of the device:
The device may be placed into a room with or without installing air channels. This influences
minimal spacing from the walls, which depend on the direction of entry and exit of air.
Figure 4: Minimal spacing between walls / ceiling in the case of air intake from the same room

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Figure 5: Minimal spacing between walls / ceiling in the case of air intake from other rooms or the
environment
In the case of using air heat from the same room where the device is installed, the room
must be at least 50 m3.
5.2 Device Levelling
WARNING
The device must be in a vertical position during operation to prevent potential
leaking of water condensation.
Figure 6: Device levelling
The device has to be levelled as shown on the image above.
5.3 Hydraulic Connection
Hydraulic connection must be carried out in accordance with the valid national and local
regulations, which are in force for the connection of sanitary water tanks. The room with the
device must have a drain below the level of the device for the drainage in the case of a water
spill. The image below shows the proper hydraulic connection of the device.

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Should the heat exhanger (heating water) in the water tank not be used for water heating, it
must be filled with an anti-freeze liquid, to prevent corrosion in the exchanger. Only close a
full exchanger at the bottom (equalisation of pressure due to temperature changes).
WARNING
Due to use of different materials on the pipe installation, all connections (cold
water, hot water, circulation, heat exchanger) on the device must obligatorily be
galvanically isolated, or the corrosion of connections within the heat storage may
occur. We recommend galvanic separators from red alloy for each attachment, at
least 2x pipe diameter in length.
WARNING
The water tank is intended for potable water so it must obligatorily comply with the
valid national regulations on potable water, or device damage may occur and the
warranty is nullified.
1
Ball valve
5
Expansion vessel
2
Pressure reducing valve
6
Drain tap
3
Check valve
7
Circulation pump
4
Safety valve
8
Device generator
3
1
1
5
6
1
1
12
3
4
7
8
Figure 7: Connection of device to plumbing network
Dimensions of expansion vessel:
Safety valve setting [bar]
6
System pressure [bar]
3,0
3,5
4,0
Volume of sanitary water tank [L]
Expansion vessel [L]*
450
35
50
50
* The actual size of the expansion vessel must be set by the installation technician / planner in regards to the size
of the system, in which the device will be installed.

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WARNING
When installing the device obligatorily place expansion vessel into the system.
WARNING
Obligatorily install safety valve onto the inflow pipe, which has a nominal
pressure of 0,6 MPa (6 bar), and prevents the increase of pressure in the hot
water storage for over 0,1 MPa (1 bar) above nominal.
WARNING
For proper operation of expansion vessel, a suitable setting of the operational
pressure of the tank must be made. The pressure is set in regards to the
pressure in the plumbing. The setting needs to be checked every 6 months..
5.4 Air Canal Installation
The device has attachments on left and right for the attachment of air canals, which enables:
the placement of the device into any room which is spacious enough
ventilation of desired room
exhaust of waste air or intake of fresh air from the environment
In the case of air canal use, keep in mind that air pipes and every additional knee represent
additional air resistance and lesser capacity of the device. Table 1 shows maximal permitted
canal lengths. Air canals must be isolated to prevent water condensation on the pipe
surfaces.
Figure 8 shows the device with air canal connections. The connections are 45 mm in length
and an outside diameter of Φ250. Access to inner parts is protected with mesh.
Figure 8: Air canal connection
Table 1: Maximal permitted air canal length.
Air canal diameter
Maximal air canal length
Diameter 200 mm
10 m
Diameter 250 mm
15 m
The final length of air canals needs to take into consideration also the equivalent length of
accessories such as knees, reduction pieces, etc.

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Table 2: Accessories
Accessories
Equivalent length in m
Knee 90° (Φ 200 mm)
3
Knee 90° (Φ 250 mm)
2
Reduction piece Φ250 x Φ200
1
Wall blind
2
5.5 Connection of Condensation Outlet
By removing heat from air, condensation of air moisture also occurs in the heat pump.
Depending on air temperature and relative air humidity, the production of moisture from air
varies. In some cases, no moisture will be removed from air and in others, up to 10 litres of
condensed water may be produced.
Attachment of pipe for
condensation outlet to the device.
Siphon for prevention of
unpleasant odour seeping from
the drain.
The water condensation outlet pipe must be laid in a way, where the water may always freely
flow out. Connect outlet pipe with drain. Should this not be possible, ensure a collection
canister, which must be regularly emptied.
NOTE
When installing a condensation outlet, pay CAUTION that the pipe is always at a
downwards incline with a siphon and water pillar of at least 5 cm at the outflow.
This prevents the suction of unpleasant odours from outlets.