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It may not be possible to completely empty collectors one they have been filled. For this reason
collectors exposed to frost should only be filled with a water/antifreeze mixture, also for pressure
and function tests. Alternatively, the pressure test can also be carried out using compressed air
and leak detection spray.
Installing the temperature sensor
The temperature sensor should be installed in the sensor sleeve nearest to the collector array
flow. To ensure optimal contact between the sensor and the surrounding environment, the gap
between the sensor sleeve and the sensor element should be filled with a suitable conducting
compound. All materials used for installing temperature sensors (sensor element, conducting
compound, cables, sealing and insulating materials) must be suitably temperature resistant (up to
250° C).
Operating pressure
The maximum operating pressure is 10 bar.
Bleeding
The system must be bled:
- when commissioning the system (after filling the collectors)
- 4 weeks after commissioning
- when necessary, e.g. if there are malfunctions
Warning:
Risk of scalding due to steam and hot heat transfer fluid!
Only operate the bleeding valve if the temperature of the heat transfer fluid is
< 60° C
.
When bleeding the system, the collectors must not be hot! Cover the collectors and, if possible,
bleed the system
in the morning.
Check heat transfer fluid
The heat transfer fluid must be checked every two years with regard to its antifreeze and pH
value.
- Check antifreeze using antifreeze tester and replace or refill if necessary!
Target value is ca. - 25° C and - 30° C depending on climatic conditions.
- Check pH value with a pH indicator rod (target value approx. pH 7.5):
If the limit pH value is less than ≤ pH 7, replace the heat transfer fluid.
Maintenance of the collector
The collector or the collector array must be inspected visually, once a year, for any damage,
leaks and contamination.
Additional recommendations on operation and maintenance can be found in the supplier's
general documentation and instructions on commissioning and maintenance.
