Should it have a little bypass hole in it?. Mine doesnt (so it is fully sealed until it reached 82C)
It is shown in the manual with a 'jiggle pin' or something similariliy named in a small hole.
Every other 'stat ive looked at in the past has had a small hole in it to let some water past, and I was wondering if making one in mine would be a good idea?
Doing so should also make it so that the temperature gauge starts reading earlier (sits at zero now until the 'stat opens and it suddenly jumps up to 80-odd) and would just seem more sensible to me as surely it means that there is no chance of the head getting airlocked or anything?