Danfoss DHP-AX User manual

USER MANUAL
DHP-AX
Navigate through the control computer’s menu using:
To increase or reduce the set values use: or
To adjust the room temperature: start by pressing
The degree information that now appears in the display is the last
desired room temperature.
To increase the temperature: press
To lower the temperature: press
The temperature you now require is registered immediately.
(After approximately ten seconds the desired room temperature
appears in the display again, together with other information.)
The heat pump now starts to work to reach the new temperature.
Want to know more? Read the User manual!
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Innehållsförteckning
Important information1 ...................................... 5
Safety precautions1.1 ...........................................5
Protection1.2 ...................................................6
About your heat pump2 ..................................... 7
Principles of function2.1 ........................................7
Components2.2 ................................................8
Heating and defrost functions2.3 ................................9
Auxiliary heat2.4 ...............................................10
Regulation information3 ....................................10
Control panel4 ..............................................18
Display4.1 .....................................................20
Menu information5 .........................................22
INFORMATION menu5.1 ........................................22
Trimming the heating system6 ..............................30
Instructions7 ...............................................31
Setting operating mode7.1 ....................................31
Setting ROOM values7.2 .......................................31
Adjusting CURVE values7.3 .....................................32
Adjusting a specific part of the heat curve7.4 ...................32
Setting MIN and MAX values7.5 ................................32
Setting HEAT STOP7.6 ..........................................33
Reading off temperatures7.7 ...................................33
Manual defrost7.8 .............................................34
Regular checks8 ............................................35
Checking operation8.1 .........................................35
Checking the water level in the heating system8.2 ..............35
Checking the safety valve8.3 ...................................36
In the event of leakage8.4 ......................................36
Cleaning the strainer for the heating system8.5 .................36
Accessories9 ................................................38
Room temperature sensor9.1 ..................................38
Troubleshooting10 ...........................................39
Alarm10.1 ......................................................39
Terms and abbreviations11 ...................................41
Default settings in the control computer12 ...................42
References13 ................................................43
Check list13.1 ...................................................43
Installation carried out13.2 ......................................44

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These instructions are valid for the following model of Danfoss heat pump:
DHP-AX
If these instructions are not followed during installation, operation and mainte-
nance, Danfoss AS’s liability according to the applicable warranty is not binding.
Danfoss AS retains the right to make changes to components and specifications
without prior notice.
© 2009 Copyright Danfoss AS.

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Important information1
DIf the installation is not used during the winter, the heating system must
be drained of water, otherwise there is a risk of frost damage to the instal-
lation. (Contact an authorized installer, see the ”13 References” section)
zThe installation can be considered maintenance free but certain checks are nec-
essary (see “8 Regular checks”).
zBefore changing the control computer’s settings, first find out what these chang-
es mean.
zContact your installer for any service work.
DThis apparatus is not intended for persons (including children) with
reduced physical, sensory or psychological capacity, or who do not have
knowledge or experience, unless supervised or they have received instruc-
tions on how the apparatus functions from a safety qualified person.
DChildren are not permitted to play with the apparatus.
Safety precautions1.1
Installation and maintenance1.1.1
AOnly authorized installers may install, operate and carry out maintenance
and repair work on the heat pump. (See the ”13 References” section)
BOnly authorized electricians may modify the electrical installation. (See the
”13 References” section)
AFATAL DANGER! Only authorized refrigeration technicians may work on
the refrigerant circuit. (See the ”13 References” section.)
System modifications1.1.2
Only authorized installers may carry out modifications on the following compo-
nents:
zThe heat pump unit

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zThe lines for refrigerant, water and power
zThe safety valve
You must not carry out construction installations that may affect the operational
safety of the heat pump.
Safety valve1.1.3
The following safety precautions apply to the hot water circuit’s safety valve with
corresponding overflow pipe:
DNever block the connection to the safety valve’s overflow pipe.
DWater expands when it is heated, this means that a small amount of water
is released from the system via the overflow pipe. The water that exits the
overflow pipe can be hot! Therefore, allow it to flow to a floor drain where
there is no risk of burning yourself.
Protection1.2
Corrosion Protection1.2.1
Due to the risk of corrosion, avoid using different types of sprays in the vicinity of
the heat pump. This particularly applies to:
zSolvents
zChlorinated cleaning agents
zPaints
zAdhesives

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About your heat pump2
Principles of function2.1
A heat pump utilises the free energy from the sun and that is found in a natural
heat source, such as rock, ground, ground water or air. The heat pump can be com-
pared to a reversed refrigerator; in a refrigerator heat
is transferred from the inside of the refrigerator to the
outside, whereas in a heat pump, the stored solar energy
that is stored in a heat source is transferred to the inside
of the house. The heat pump uses the solar energy in the
heat source and gives back two to three times more heat
energy than it uses in electrical energy. The heat pump is,
therefore, a very environmentally friendly and economical
way of heating a house.
Figure 1: The relationship between consumed electrical energy and free solar energy.
In order for the heat pump to be able to retrieve heating energy from the outdoor
air and transfer it to the heating system of the house, two separate liquid circuits
are required. The figure below shows the different circuits and how they work
together in the transfer of heating energy.
Figure 2: Function principles of a heat pump.
Expansion valve/
pressure drop
Enclosed
refrigerant
Compressor/
pressure increasing
Water
Fan
Condenser
Air heat exchanger
Heating system – is the circuit that con-
tains the water that transports the heat/
energy to the heating system and the
water heater.
Refrigerant circuit – is the closed circuit
that contains a chlorine and freon free
refrigerant that inside the heat pump,
transfers the retrieved heat energy to the
heating system through evaporation,
compression and condensation.
Outdoor air
Heating system

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zA fan draws up the outdoor air through an air heat exchanger, which heats up
the cold refrigerant, which evaporates into a gas. The energy produced during
this process is retrieved from the passing outdoor air.
zThe refrigerant that now supplies energy in the form of heat is transferred to the
compressor, which both increases its temperature and pressure.
zThe extremely hot refrigerant continues to the condenser. Here, the refrigerant
is cooled and releases its heating energy to the heating system. The refrigerant’s
temperature drops and condenses to a liquid state.
zThe heating system transports the heating energy out to the water heater or the
heating system, which indirectly heats the house.
zThe refrigerant is then transported through the expansion valve where the pres-
sure and temperature drop and the process starts again.
Components2.2
DHP-AX is a complete heat pump installation for heating. It can be supplemented
with a water heater and auxiliary heater.
DHP-AX is equipped with a control system, which is controlled via a control panel.
Heat enters the house via a water borne heating system.
The heat pump unit consists of the following basic units:
1 Heat pump unit
zCompressor
zCondenser
zFour way valve
2 Fan
zOne speed
3 Air heat exchanger
In addition to these units, there is control
equipment (installed indoors), which controls
the heat pump unit’s component parts (com-
pressor, circulation pumps, auxiliary heaters
and exchange valve) and determines when to
start and stop the pump as well as whether to
produce heat for the house or hot water.
Figure 3: DHP-AX’s main components.
1
2
3

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Heating and defrost functions2.3
Heating2.3.1
DHP-AX is a heat pump that produces heating for houses and water heaters
depending on the existing demand. Hot water production is continuous but during
the summer heat production to the house is stopped when the outdoor tempera-
ture reaches the value for HEAT STOP.
During the winter, hot water and heat is produced for the house by the compres-
sor until the outdoor temperature reaches the value for OUTDOOR STOP when it
becomes too cold for the compressor to operate. If an auxiliary heater has been
installed, it is used to produce hot water and heating for as long as OUTDOOR STOP
applies.
DHP-AX defrosts the air heat exchanger automatically if required.
Defrost function2.3.2
During operation the air heat exchanger is cooled by the energy exchange at the
same time as the humidity causes it to become covered in frost. DHP-AX has an
automatic function to defrost the air heat exchanger using the produced heat ener-
gy. If necessary, a defrosting sequence starts which means the following:
zThe defrost sequence starts when the temperature of the incoming refrigerant is
lower than the set value, which is based on a curve that is related to the outdoor
temperature
zThere are restrictions for the defrost regarding time in operation and FAN on
zThe four way valve in the heat pump switches the direction of flow of the refrig-
erant and the fan stops, see figure below
zThe hot refrigerant melts the frost on the air heat exchanger
zDefrost stops on time, operating pressostat or incoming temperature.
zThe four way valve switches the direction of flow of the refrigerant back so that
heat production resumes and operation returns to normal
The process is reversed by means of the four way valve that changes the direction
of flow, which means that the air heat exchanger for heating becomes a condenser
and the heating’s condenser becomes an evaporator. This function is used for
defrosting.
As the heat pump’s defrosting sequence retrieves its energy from the house’s
heated heating system during the winter months, the water tank is primarily used
as a heating buffer. If a water heater is not installed, the water volume in the heating
system must be increased by installing a surge tank (accessory).

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Auxiliary heat2.4
Auxiliary heater is an option for DHP-AX and consists of an immersion heater, which
is located on the supply pipe ahead of the exchange valve.
The auxiliary heater, which is supplied as an accessory has an integrated power con-
trol and is controlled by a potential free output from the heat pump. In the event of
power cuts longer than three minutes, only a 6 kW output may be connected imme-
diately after power has returned, the remaining output is delayed two hours.
If the auxiliary heater is installed it engages AUTO mode automatically when the
heat demand is greater than the heat pump’s capacity.
In the event of alarms that mean that the compressor does not start, hot water will
not be produced in order to indicate to the customer that something is wrong. Heat
is produced by the auxiliary heater so that the house does not become cold.
Regulation information3
Heat production - calculating3.4.1
The indoor temperature is adjusted by changing the heat pump’s heat curve, which
is the control system’s tool for calculating what the supply temperature should be
for water that is sent out in the heating system. The heat curve calculates the sup-
ply temperature depending on the outdoor temperature. The lower the outdoor
temperature, the higher the supply temperature. In other words, the supply tem-
perature of the water fed to the heating system will increase exponentially as the
outside air temperature falls.
The heat curve will be adjusted in connection with installation. It must be adapted
later on, however, to obtain a pleasant indoor temperature in any weather condi-
tions. A correctly set heat curve reduces maintenance and saves energy.
CURVE3.4.2
The control computer shows the value for CURVE by means of a graph in the char-
acter window. You can set the heat curve by adjusting the CURVE value. The CURVE
value indicates the supply temperature of the water to be sent out to the heating
system at an outdoor temperature of 0°C.