What are the 2 silver metal boxes attached to the pipes at the front/bottom of the photo. I'm guessing thermostats.
Basically, when I switch on the hot water, there is a loud clicking/buzzing sound coming from one of them. Should I get them replaced? The hot water and heating still works.
Basically, when I switch on the hot water, there is a loud clicking/buzzing sound coming from one of them. Should I get them replaced? The hot water and heating still works.