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Please check your solar collector according to the following list. In case there are still problems after the check or the energy output is not sufficient, please contact our service team.

  • Does the collector have the correct orientation?

Chek the correct southward deviation, the inclination angle of the roof, whether the collector is covered by shade and whether the tubes are installed with optimal inclination angle.

  • Is the collector correctly installed?

Are the tubes inserted into the header box? Is the manifold tightly fastened and stable? Are the collector modules connected in series or according to the technical design?

  • Is the heat transmission paste correctly applied?
  • Are the vacuum tubes in perfect state?

Are the glass tubes broken or cracked? Is condensed water in the tubes? Is the selective coating fading upward? The vacuum is likely to be lost if the surface temperature of the glass is 10K higher than the ambient temperature. In this case the old tubes have to be replaced.

  • Are all tubes insulated?

Check whether hot water pipe, circulation pipe, pipe of solar loop, storage tank and relevant fitting are all well insulated.

  • Is the right heat transfer medium liquid used?

Only high temperature and anti-freezing medium should be used (Tyfocor LS or a comparable one), the PH-value should not be lower than 7.

  • Is the sensor of the collector in the right position?

The sensor of the collector must be installed on the outlet pipe of the collector (warm water side) and must be completely inserted into the manifold.

  • Is the sensor of the storage tank in the right position?

The sensor must be installed on the output pipe of the hot water.

  • Is air in the system?

In case there is an air-noise when the pump is turned on and shut off, outgassing has to be done. The manifold should be at the highest position of the collector or an auxiliary air-vent has to be installed.

  • Is the maximal area depended flow correctly adjusted?

First, the controller has to be set into the manual operation mode (100% pump output). Then the desired maximal area depended flow has to be adjusted.

Rule of thumb for the area depended flow:

Collector system for the preparation of warm water: 40l/h x m² absorber area = area depended flow

Through reduction of the area depended flow the desired temperature enhancement of the heat transfer medium can be achieved.

Collector system for heating 25l/h x m² absorber area = area depended flow

  • Is the operation point of the controller correctly adjusted?

Check whether it has been properly adjusted in advance. If the lowest temperature of the collector is too high the controller has to be changed.

  • Does the sensor have a correct measuring value?

Check the measured value and measure the resistance. Compare the measured value with the specific value of the sensor.

  • Is an unloading of storage taking place at night through gravity self-circulation?

The temperature of the thermometer which is installed in the solar loop should not increase at night.

  • Is the operation time of the drinking water circulation pump adjusted in the
    optimum state?

Adjust the operation time of the pump to the optimum if this is not the case.

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