Here you can quickly find answers to frequently asked questions.

By pressing the text

CAUSE:If the evaporator falls below 19°C the heat pump stops. Alarm no. 4 appears in the display.
The temperature is outside the heat pumps working area.
ANSWER: The supplementary heating should take over the heating process. By gas defrosting, check the solenoid valve opens during defrost. Wait until the temperature is within the heat pumps working area.
CAUSE: It is because of high humidity in the intake air. This does not affect the heat pump operations. This will typically happen the first time the heat pump is started. It can also occur if wet clothes is hung up for dry in the same room as the heat pump takes air from.
CAUSE: The heat pump can deliver approx. 320L hot water in a stretch of 40°C hot water at a starting temperature of 55°C in the tank. If the need for hot water is higher, the heat pump cannot keep up. The heating rod will help heating, if it is connected.
ANSWER: Check if the heat source combined with the heating rod is activated.
CAUSE: Check the heat pump are leveled.
Check defrost water runs down properly into the defrost tray.
Check that the drain hose from defrost drain is not stopped.
ANSWER: Put the heat pump in correct level.
Mount the defrost tray correctly.
Clean the drain hose.
CAUSE: If the display has been removed and not installed properly on the base print.
Static electricity can turn the display off.
ANSWER: Mount the display connector correctly in the base print.
Replace the display. Check that the ground wire is properly mounted to the upper door.
CAUSE: Check fuse.
Check that the power plug is plugged into the socket on the wall.
Check if the power switch on the wall is turned on.
Check if the heat pump is switched on.
ANSWER: Change the fuse if necessary.
Put in the plug into the socket.
Turn on the power switch.
Turn on the heat pump.
CAUSE: There is a built-in delay of 5 min. from the compressor stops to a new start. Only for models with electronic control.
ANSWER: Wait 5 min. and check the compressor again.
CAUSE: There is connected radiator / floor heating to the heat pump and the need for heating is larger than the heat pump can keep up with.
The evaporator is stopped.
There may be a leak in the cooling system, all or some of the coolant is lost. Check temperatures in the cooling system. See schema for curvatures of temperature.
ANSWER: Mount the thermostat so that hot water has always the first priority.
Clean the evaporator gently with clean water.
Locate the leak and repair it, fill with coolant. Quantity: See model type.
CAUSE: Sensors are not correctly placed into sensor pockets.
Sensors must be placed at the bottom of sensor pockets.
ANSWER: Put the sensors correctly into sensor pockets.
CAUSE: There will be condensation during heating cycle. It happens when the surface temperature at the evaporator is below dew point temperature of the inlet.
ANSWER: Condensate water is collected in the defrost tray and passed through the attached defrost hose to floor drain.
CAUSE: The ambient temperature is higher than +35°C and the cooling system drops out on the high pressure thermostat.
The cooling system has reached its maximum temperature. This may be due to little or no air flow over the evaporator..
ANSWER: Wait for lower ambient temperatures and activate the high pressure thermostat by pressing the reset button.
Clean the evaporator gently with clean water.
Set the fan speed to max.
Enable the high pressure thermostat.
CAUSE: The cooling system has reached its maximum temperature and drops out on the high pressure thermostat. The maximum continuous temperature must not exceed 55°C. The legionella function will one time per week increase the temperature to 65°C.
ANSWER: Replace the thermostat / sensor if defective.
Activate the high pressure thermostat by pressing the reset button.
CAUSE: When water is heated it expands and the water pressure increases. The security group on the cold water pipe prevents the water from running backwards. The valve will take over the pressure by letting some water run out. The pressure in the tank should never exceed 10 Bar.
ANSWER: It is normal that sometimes water comes out of the safety valve during the heating cycle.
CAUSE: Operating thermostat is set too low.
ANSWER: Set the operating thermostat to a higher temperature.
CAUSE: It takes approx. 8 hours at 20°C air temperature to heat the water up to 55°C. At lower temperature, it takes longer time.
ANSWER: Switch off the radiator / floor heating cycle, if one is installed. If necessary turn on the supplementary heating. Heating rod / boiler.
CAUSE: Is there light in the panel.
ANSWER: Turn on the heat pump.

Vesttherm is a Danish owned manufacturer of hot water heat pumps. For more than 30 years, we have produced high quality products throughout Europe.

We are known for our high quality, our high flexibility and our ability to produce customized solutions.

Vesttherms product range includes many different consumer solutions tailored to our customer's needs.

All of Vesttherms employees work with great effort on quality, product development and design. This greatly helps to strenghen our competitiveness

Contact information

Øresundsvej 10
DK-6715 Esbjerg N
Phone +45 75 14 02 44
VAT: 26993601