What are these chimney connections?

[Skånepåg]

Hello!

I have three connections to my chimney that are no longer used. They are essentially just holes leading directly into (probably) different flues, but still...

The top one is what I guess is just ventilation to bring in new air for the old boiler. Am I right?

The next one is sealed with some kind of flange/fitting. Do you think one can remove the fitting to seal the hole more neatly, or is it some kind of connection flange on a long iron pipe (which in that case can't be pulled out)?

In the next hole, there is still ash remaining. I also plan to seal this one.

In the top and bottom ones, there is draft out of the house. I was planning to leave the top one as is while sealing the two lower ones. Would sealing these be bad for the chimney?

Best regards,
Mats

 

[v-g]

Could be an old "vadsomhelst" I have a hole for a water heater, i.e., the kind you used to boil water in for washing.

It's just a matter of bricking it up as long as you don't plug the channel inside.