We have underfloor heating installed with heatmiser UH8-RF and Grundfos UPM3 Flex As pump and Honeywll 272848 motorized valve.
It was working fine for nearly year and now it has started blowing surge fuse 5am 250v,(Fuse-2) in UH8-RF. Enire system is new and not sure why it is keep blowing surge fuse.
The person who installed it not willing to come now as he has moved to 200 miles away and before I call someone just want to know what could be an issue.
Many thanks,