The 18-year-old stopper is making his first move away from Wolves, having been a regular at under-18 and under-21 level since he switched to England from his native Iceland back in 2019.
An Icelandic under-19 international, Arinbjornsson also signed a new contract with his parent club before heading to the Norwegian First Division - which came just 24 hours after he helped Wolves under-21s to their win over Shrewsbury Town in the Papa John's Trophy on Tuesday night.