Since it got cold again, we have been getting the error message “Safety time expired, oxygen content too high for too long” repeatedly, usually on a daily basis, which means that the heating stops working until the error is acknowledged. This is very annoying and very cold if you don’t notice immediately that this error has occurred (our heating was offline until recently).
After searching the internet, I haven’t found a clear answer. The message is also strangely worded:
Translated, it means that the fire should be lit, but the sensors are measuring too much oxygen and therefore it is assumed that no fire could be lit. You have to figure that out first.
The error can therefore have many causes: The sensor that measures the fill level in the pellet buffer tank in the heating system may be defective or malfunctioning, something in the ignition or feed system may not be working properly, and so on.
That wasn’t it!
The problem could probably have been quickly resolved with the help of a competent heating engineer experienced with Fröling systems, but we don’t have access to one at the moment. So we spent weeks struggling to fix this error, and our solar expert even had to wire the internal components of the meter cabinet in the cold.
The solution is very simple and, in retrospect, logical:
I don’t know what the factory setting is, but you can set the times at which pellets should be drawn to fill the internal buffer storage tank. This makes a lot of sense because it means that the system is not sucked dry in the middle of the night.
There are two times, and in our case both were set to “0:00”!
This means that suction should only take place once a day, namely at night. Or as needed?
Good question. In any case, an internal buffer storage tank was obviously not sufficient for our house and ran empty before it could be refilled every 24 hours. The first time is now set to 12 noon, the second to 10 p.m.
Since then, the error has never occurred again!
