Sealant around skim plug?

Motorapido

I'd like to skim my steam boiler (new owner of old house with 6-year-old Burnham steam boiler -- dunno what installer did or did not do) and need to double-check about opening the system to skim from the top of the boiler. Just above and to the right of my water level sight glass, there is a plug with a square head on it that threads into the boiler. The square head stands just a wee bit outside of the metal panel exterior of the boiler. First, please confirm that that plug would be the plug to remove for skimming. Second, please comment on the sealant that I see around the threads of that plug. There is a thick green sealant material that is very firm to the touch. It feels like plastic or very hard wax. I cannot smoosh it with my finger and my fingernail does not create a score in it when I press it hard. Why would sealant be necessary on NPT threads, other than a thick wrap of teflon tape? Any danger in removing that plug if some of that green sealant drops into the boiler? And although the sealant is very firm, will the plug remove easily, or will that sealant act like a thread lock or glue and would I risk boiler damage by trying to remove the plug?

ChrisJ

Motorapido said:

I'd like to skim my steam boiler (new owner of old house with 6-year-old Burnham steam boiler -- dunno what installer did or did not do) and need to double-check about opening the system to skim from the top of the boiler. Just above and to the right of my water level sight glass, there is a plug with a square head on it that threads into the boiler. The square head stands just a wee bit outside of the metal panel exterior of the boiler. First, please confirm that that plug would be the plug to remove for skimming. Second, please comment on the sealant that I see around the threads of that plug. There is a thick green sealant material that is very firm to the touch. It feels like plastic or very hard wax. I cannot smoosh it with my finger and my fingernail does not create a score in it when I press it hard. Why would sealant be necessary on NPT threads, other than a thick wrap of teflon tape? Any danger in removing that plug if some of that green sealant drops into the boiler? And although the sealant is very firm, will the plug remove easily, or will that sealant act like a thread lock or glue and would I risk boiler damage by trying to remove the plug?

Some pictures would be nice.

Motorapido

Ask, and ye shall receive. The green goo around what I think is the skim plug.

Motorapido

Here is the plug in context

Fred

Are you sure that's a Burnham boiler? The only way to determine if it will be easy or difficult to remove is to put a wrench on it and try turning it. It looks like it should be relatively easy but you just don't know until you try.

Motorapido

Confused with other system. It's peerless.

Fred

Motorapido said:

Confused with other system. It's peerless.

That's more like it. There should be a larger knock-out in one of the panels somewhere around that boiler at about that height and a larger plug behind that knock-out (maybe 1.5"). The bigger the tapping the more effective the skim.

Motorapido

Thanks. Only other taps are below water line. Real big one by low water blow down. Smaller one over toward front, Below and and to left of pressuretrol pigtail.

Motorapido

Head on the one I'm thinking is skim plug is 1 inch square.