Error code "Err 03" (Inverter and Nano models)


Problem :

Your control box displays the error code "Err 03", and your heat pump no longer works.

Origin of the problem :

This problem corresponds to a malfunction of the flow detector.

Resolution :

This can correspond to 3 causes:

1 - You do not have enough water in the heat pump water circuit (the heat exchanger). You must check the proper circulation of water within the heat pump. To do this:

- Check that your pool filter or circulating pump is working properly and if necessary, re-prime it (see your MSI)

- Check that the water inlet and outlet pipes are connected correctly (in the right direction)




2 - Water flow sensor is faulty

The water flow sensor prevents the heat pump from overheating. The sensor is a blade located at the outlet of the heat exchanger.



- Check that the direction of the blade is correct with the arrow on the sensor indicating the direction of circulation of the water.


If the direction is not good follow the following procedure :

* Turn off your filter pump.

* Unscrew the sensor.

* Press in the direction of the arrow on the sensor until the Heat Pump starts.



If it starts, the problem is your water circulation (cause #1 – above).

If it does not start, go to point 3.

3 – Water flow sensor is disconnected

* Unplug the heat pump electrically.

* Unplug the heat pump electrically.

* Open the heat pump top cover.

* Open the electrical box cover to access the electronic board.

 * Check that the terminals of the "fluxostat" or "water flow switch" are connected (diagram). The position of the sensor is indicated on the electrical diagram of your manual (Water flow switch in IN4 for Inverter models).

Diagram for the NANO model:


- If the terminals are not properly connected, please reconnect them correctly.

- If the terminals are well connected, the sensor is probably faulty and needs to be changed.

In case your product is out of warranty (more than 2 years or more than 3 years for Jetline Premium only), you can order the spare parts on our website.

If your product is still in warranty (less than 2 years or less than 3 years for Jetline Premium only), fill out the form, attaching your purchase invoice and a picture of the problem as an attachment.

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