What size vent should these be replaced with?

bbillcee

this is an elevated rad at the end of the line above this is your standard vent, this vent is on top of the return, it’s 3/4 pipe ( this part of return is really only for this rad.) i dont think its working cause the top part of the rad gets hot where the other vent is but the bottom half where this is stays only warm 🤷🏻‍♂️

this next one is a main vent. Its vents about 30 ft of 2 inch see below. Whatever size it is it seems to be ok because the pipe gets hot pretty quick.. but i think its staying open once n a while a venting steam.

Steamhead

How long are those steam mains, and what pipe size?

bbillcee

The steam main is about 30 ft of 2 inch, the first picture is on the return pipe 3/4 inch it’s about 10 ft after that main in the 2nd picture.