Corroded Boiler part?

[exm]

I have a Weil-McClain cg-25-spdn boiler which works fine. Upon annual cleanup (which I always do) I noticed this part corroded. I am not sure what it is, if it's normal and if I should have this replaced? What are your thoughts? Much appreciated!

 

[johnjh2o]

It's a automatic vent.
http://www.taco-hvac.com/en/products/Air Vents/products.html?current_category=87

 

[exm]

It's a automatic vent.
http://www.taco-hvac.com/en/products/Air Vents/products.html?current_category=87

Thanks!

Should it look like this? Or does it need to be replaced?

 

[johnjh2o]

It needs to be replaced before the next heating season.