Kontrolle Einstellung Umschalttemperatur UV- Rücklauf F2

Deutsch > Englisch Technik Wirtschaft/Handel (allgemein) HACCP- Kontrollemaßnahme

"Kontrolle Einstellung Umschalttemperatur UV- Rücklauf F2"
The above is listed as a control measure. Firstly i can't document "UV- Rücklauf F2" anywhere and secondly, due to the lack of punctuation, the word order is tricky. Here is my effort:

"Switch-over temperature setting control UV return F2"
I have gone with "return" for "Rücklauf" as i really don't know what is meant.

Any ideas?
Thanks,