Magnetic Filter........

[John.g]

Saw this briefly, installed on a Glowworm boiler, what is the orange graduated knob for?, the arrow above it is pointing downwards but if the M.filter is on the return then the flow will be upwards.

 

[John.g]

I learn something new every day, if you click on the image (post #1) then right click to bring up the menu then select "image wih google" (google lens) it identifies it as a BI-World M.Filter, the orange knob is a Servicing Date Wheel.

 

[Ben-gee]

As it’s 12 graduations and looks a “dumb” knob, I’d guess it’s used to indicate which month service is due- as simple as that !!