Rust welded main vent

iizbor3d

Trying to replace a leaky steam main vent, but I'm having trouble removing it. Besides being rust welded on, the installer hasn't used any Teflon or any paste. I've tried using PB blaster, applying torch heat and a 14" wrench. I've removed the 2nd vent, from the last picture, in a better looking condition with a 6ft pipe for leverage. I'm afraid to do the same with this vent due to the condition of the elbow also. Can't afford to break that elbow off during the heating season. The basement was flooded by hurricane Sandy and when NYC build it back program came to do repairs they cut as much of the old main out and coupled it to the old rusty main. They definitely didn't replace these vents. Any advice for other techniques to try? 

RTW

You may want to try "Kroil penetrating oil" that some say works better than PB Blaster. I had a similar main vent issue and the vent itself self-destructed in the process of trying to remove it, but it came off.

iizbor3d

I'll give that a shot thank you! What do you mean by self destructed? Did the vent just separate? 

fueloilrich631

1st problem is the PB, its garbage.
Kellogs penetrating oil, kroil, seafoam penetrating oil, or 50/50 mix of acetone and ATF are all far superior
In the past, i have used them all with a combination of heat and tapping with a hammer and enough leverage with success.

Jamie Hall

That's not really an very good location for a vent... give up and put a new one somewhere else?

iizbor3d

fueloilrich631 said:

1st problem is the PB, its garbage. Kellogs penetrating oil, kroil, seafoam penetrating oil, or 50/50 mix of acetone and ATF are all far superior In the past, i have used them all with a combination of heat and tapping with a hammer and enough leverage with success.

Good to know! I have seafoam I'll give that a shot also. 

iizbor3d

Jamie Hall said:

That's not really an very good location for a vent... give up and put a new one somewhere else?

The vent is leaking steam needs to be removed anyway. 

ethicalpaul

Sorry to be a contrarian, but that's an OK location. The "slug of water" idea is a myth except in case of heavy surging, where the water level of the boiler drops significantly from gallons of water being injected up into the main.

And that condition should never occur except in extreme cases of oily/bad water and/or very badly piped boilers, both of which should be remedied and not allowed to occur, and once fixed, don't recur. Moving it back from the corner and above the main doesn't hurt of course, but the gain is marginal.

In actual normal operation, a gentle trickle of condensate starts at the beginning of steam production, and increases in a controlled way over a relatively short time period as the boiler starts producing its rated amount of steam. The water doesn't rage, it doesn't slosh or splash, it just flows. The water likes to stick to the pipe.

Larger systems (properly piped) have correspondingly larger mains, and they handle the volume with no problem.

It would be cool if that one weirdly-oriented reducing tee were rotated, you can work on freeing that up after you get the vent off

WMno57

If I had to remove that vent I might cut off the body with a sawzall or hacksaw. Then put an impact socket on the hex and use an air impact wrench. Sometimes it helps to rattle it in both directions to break it loose.
Not a lot of room to work there. Might need swivel socket or a short swivel adapter too. Here is a stubby impact wrench.

https://www.harborfreight.com/automotive/impact-wrenches/air-impact-wrenches/12-in-stubby-air-impact-wrench-jumbo-hammer-700-ft-lbs-63534.html

WMno57

After you cut the vent body off, you might also be able to drill and tap the hex for a pipe plug.

109A_5

Hello @iizbor3d,
You need another (2nd) long wrench orientated properly to carefully hold the street elbow in place when applying the torque to the air vent valve hex to remove it. So that the torque to remove the air valve is not applied through the street elbow to the heal tee and to the main, which as you stated may break off the street elbow.

If you cut off the air vent valve (above the hex) and put multiple cuts into the threaded area like in the video, it take the strength out of the threaded part of the air vent valve. I would not hammer on the street elbow much as long as it is intact. Take your time and be careful. Don't cut into the threads !!!

If bad things happen or if you just want use this technique in the video to get the threads out of the heal Tee (broken off street elbow).

Steam Radiator Valve Leaking
https://youtu.be/Fr9hFxuxWss

iizbor3d

WMno57 said:

If I had to remove that vent I might cut off the body with a sawzall or hacksaw. Then put an impact socket on the hex and use an air impact wrench. Sometimes it helps to rattle it in both directions to break it loose. Not a lot of room to work there. Might need swivel socket or a short swivel adapter too. Here is a stubby impact wrench. https://www.harborfreight.com/automotive/impact-wrenches/air-impact-wrenches/12-in-stubby-air-impact-wrench-jumbo-hammer-700-ft-lbs-63534.html

That is actually a great idea! Will be a great backup plan if penetrating fluid doesn't work. 

iizbor3d

109A_5 said:

Hello @iizbor3d, You need another (2nd) long wrench orientated properly to carefully hold the street elbow in place when applying the torque to the air vent valve hex to remove it. So that the torque to remove the air valve is not applied trough the street elbow to the heal tee and to the main, which as you stated may break off the street elbow. If you cut off the air vent valve (above the hex) and put multiple cuts into the threaded area like in the video, it take the strength out of the threaded part of the air vent valve. I would not hammer on the street elbow much as long as it is intact. Take your time and be careful. Don't cut into the threads !!! If bad things happen or if you just want use this technique in the video to get the threads out of the heal Tee (broken off street elbow). Steam Radiator Valve Leaking https://youtu.be/Fr9hFxuxWss

Thank you for the suggestions! I've had two pipe wrenches when I tried removing it. But the amount of corrosion on that elbow still made me really nervous. Last resort is to carefully cut the threads from the inside if I break the vent off or break the elbow. 

reggi

I'd put a 3'-4' pipe wrench on that street ell from underneath and use leverage to turn the whole thing out... At least I'd give that a shot...
Edit: jaws open facing up

iizbor3d

The jaws of the wrench wouldn't crush the elbow? I'm not sure how bad the corrosion is. 

iizbor3d

Update, seafoam deep creep worked like a charm. Thanks everyone!