This FAQ support page provides solutions to the most common problems.
If you cannot find a solution to your problem using the FAQ support catalog, please use the support contact form at the bottom of this page . The fothermo team will then contact you to find a suitable solution together.
Solution : Connect photovoltaic modules to the boiler. The display will be powered by photovoltaic electricity. The display will then show the current hot water temperature.
If the display remains off, please press the ON button on the right side of the display for 5 seconds .
If the display is still off, please check the electrical connection and the correct polarity of the photovoltaic module to the boiler.
If nothing helps, please fill out the support form.
IMPORTANT: Please disconnect all power cables from the solar boiler and take the boiler out of service. There is likely a fault with the circuit board.
Cause : The cause is usually a (temporary) series connection of the photovoltaic modules when connecting the modules to the solar heating element. Due to high voltages, the electronics have been damaged.
Solution: Please contact the fothermo support team using the support form. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronics unit for the solar heating element. To ensure prompt processing, please describe the cause of the problem (e.g., series connection of the PV modules) in the support form.
Solution: It is possible that a cable inside the boiler has come loose or that the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
Solution: It could be that a cable inside the boiler has come loose, the heating element has burned out (unlikely), or the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
Solution: Check if you can lower the temperature using the thermostat on the boiler. To do this, set the dial to, for example, 45°C and check if the water cools down slowly. If it does, the boiler is working correctly.
If this is not the case, please use the support form so that we can quickly resolve the problem together.
There is likely a defect in the circuit board. The cause is usually a (brief) series connection of the photovoltaic modules when connecting them to the solar boiler. Due to high voltages, the electronics have been damaged.
IMPORTANT: Please remove all photovoltaic modules from the solar boiler.
Solution: Please contact the fothermo support team using the support form. We will get in touch with you. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronic control unit for your solar boiler. To ensure prompt processing, please describe the cause of the problem (if known) in the support form.
No, it's perfectly normal for the valve to drip. It can start dripping especially when the water expands significantly due to a sharp increase in temperature. Make sure the escaping water can drain away properly.
Solution : Restart the switching device by disconnecting all photovoltaic modules from the switching device.
If the display error persists, please fill out the support form. Describe your problem and send us a photo of the faulty display. This issue can be resolved with a minor software update.
Solution : The switching device is too hot. Place the device in a shady and cool location.
If this does not resolve the issue, please use the support form at the bottom of this page.
Solution : Please check all connections on the switching device. Could there be a short circuit at any point?
The switching device may enter "SHORT DETECTED" mode if unsuitable products are connected to its outputs. Please check compatibility.
If the above solutions do not help, please contact us via the fothermo support form at the bottom of this page and let us know which photovoltaic modules and electrical appliances you have connected to the switching device.
Solution : Press and hold the ON button on the right side of the display for 5 seconds.
If the display is still off, please check the electrical connection AND the correct polarity of the photovoltaic module to the solar heating element.
If nothing helps, please fill out the support form.
IMPORTANT: Please remove all photovoltaic modules from the solar heating element. There is likely a defect in the circuit board.
Cause : The cause is usually a (temporary) series connection of the photovoltaic modules when connecting the modules to the solar heating element. Due to high voltages, the electronics have been damaged.
Solution: Please contact the fothermo support team using the support form. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronics unit for the solar heating element. To ensure prompt processing, please describe the cause of the problem (e.g., series connection of the PV modules) in the support form.
Solution: It is possible that a cable inside the solar heating element has come loose or that the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
Solution: It could be that a cable inside the boiler has come loose, the heating element has burned out (unlikely), or the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
IMPORTANT: Please remove all photovoltaic modules from the solar boiler. There is likely a defect in the circuit board.
Cause : The cause is usually a (temporary) series connection of the photovoltaic modules when connecting the modules to the solar heating element. Due to high voltages, the electronics have been damaged.
Solution: Please contact the fothermo support team using the support form. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronics unit for the solar heating element. To ensure prompt processing, please describe the cause of the problem (e.g., series connection of the PV modules) in the support form.
Solution : Connect photovoltaic modules to the boiler. The display will be powered by photovoltaic electricity. The display will then show the current hot water temperature.
If the display remains off, please press the ON button on the right side of the display for 5 seconds .
If the display is still off, please check the electrical connection and the correct polarity of the photovoltaic module to the boiler.
If nothing helps, please fill out the support form.
IMPORTANT: Please disconnect all power cables from the solar boiler and take the boiler out of service. There is likely a fault with the circuit board.
Cause : The cause is usually a (temporary) series connection of the photovoltaic modules when connecting the modules to the solar heating element. Due to high voltages, the electronics have been damaged.
Solution: Please contact the fothermo support team using the support form. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronics unit for the solar heating element. To ensure prompt processing, please describe the cause of the problem (e.g., series connection of the PV modules) in the support form.
Solution: It is possible that a cable inside the boiler has come loose or that the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
Solution: It could be that a cable inside the boiler has come loose, the heating element has burned out (unlikely), or the mechanical safety temperature limiter in the boiler has been triggered.
Please contact us via the support form so we can resolve the problem quickly.
There is likely a defect in the circuit board. The cause is usually a (brief) series connection of the photovoltaic modules when connecting them to the solar boiler. Due to high voltages, the electronics have been damaged.
IMPORTANT: Please remove all photovoltaic modules from the solar boiler.
Solution: Please contact the fothermo support team using the support form. We will get in touch with you. After a brief analysis of the hardware and software, we can usually quickly identify the fault and offer you a new electronic control unit for your solar boiler. To ensure prompt processing, please describe the cause of the problem (if known) in the support form.
No, it's perfectly normal for the valve to drip. It can start dripping especially when the water expands significantly due to a sharp increase in temperature. Make sure the escaping water can drain away properly.
Solution : Please contact us via the support form. We will resolve the issue quickly and easily together.
