Drilling & Tapping Cast Iron Tee To Install A Gorton #2 Steam Main Vent. Letting The Air Out!

Getting rid of the air from a coal era steam heating system as quickly as possible is the secret to making them work so much better!
There is very little commentary on this video because this process has to be done right the first time and requires the worker to be focused and not distracted.
The fitter first drills an 1/8" pilot hole in the chosen location, roughly in the middle of the last tee on the system.
A slightly bigger hole is drilled using a standard drill bit.
A step bit (1/8" to 1/2") is used to widen the hole.
Notice the oscillating motion of the 1/4" impact driver by the operator and the slight upward angle of the drill.
The process is repeated using a larger step bit up to 3/4"
A 1/2" NPT tap in a socket of the correct size and a 1/2" ratchet makes the threads in cast iron.
Please notice the steam fitter carefully tapping the 1/2 NPT threads to just the right depth.
This process takes several times to dial it in, as threading too deep would make it much harder to make a good seal on the 1/4" thick cast iron fitting.
No cutting oil is used as the old cast iron has plenty of lubricating graphite already in the metal and any oil may contaminate the boiler water.
The technician pipe dopes a short 1/2"steel nipple (off screen) and installs a recovered 1/2" cast iron 90.
Finally, he installs it in the newly formed hole using a short pipe wrench so as not to over-torque the iron and threads on a Gorton #2 in the 90 fitting.
During the coal era, main vents on these small systems were thought not to be needed (& it kept the install price low) because the coal fire would burn for hours and hours and hours and eventually the air was driven from the system and the radiators would finally heat.
Always keep in mind that Steam and Air are invisible gasses that Do. Not. Mix.
Where there is trapped air, steam cannot flow and do its magic of making radiators warm.

[@briancrandall1601]

Very impressive. I have seen a lot of drains connected to cast iron pipe by drilling and tapping. When I was a apprentice I saw a sump pump pipe was connected to the fresh air vent for a house trap and it was drilled and tapped too.

[@mikec5513]

Now after all these years the system works. The harder part is knowing how to fix it. Nice job.

[@robertzacks3002]

Excellent! You make it look easy. Thank you for sharing!

[@gordonschweizer5154]

You are welcome!

[@darwinmedrano6834]

Nice work but you swallowed all that asbestos in those pipes.

[@gordonschweizer5154]

I eat asbestos for breakfast Rust for lunch Soot for supper Bon appetit

[@pwner4once]

Great work! I have single pipe steam system as well and miss seeing videos about it.

[@gordonschweizer5154]

Thanks! You've come to the right channel right here for steam heating videos.

[@jakeW1955]

Awesomeness is no accident, finally we see the magic!

[@shytown2406]

Where exactly should I install this Air Valve in the system?, I have a steam single pipe radiator system

[@gordonschweizer5154]

A main air vent on a single pipe steam system is generally installed near the end of the main. As to where exactly would depend on your system's unique circumstances.

[@dannywilkins887]

Nice job!

[@nybiggs]

Thanks for the excellent directions. How difficult would this be to get right for someone who has never done it?

[@gordonschweizer5154]

That's a hard question for me to answer. It is difficult, if not impossible, to convey mechanical "feel" on ytube. I myself would not advise doing this unless you don't need the heat for awhile in case of mishap.

[@nybiggs]

@@gordonschweizer5154 Thank you for your honest answer!

[@randyjardee7024]

Good work, I watch all your Utubes and wish there were more. I have been only brave enough to tap 1/4" on the top of 2" IPS. I would put two taps in a couple of feet apart for G2's. If I understand the Dan books a 1/4" tap will handle a G-2. Think that is a good guess? BTW, I see that Gordo, Frank and myself all have the same hairdresser.

[@aglasserm1679]

That does look like asbestos insulation on that pipe! Nice Job!

[@gordonschweizer5154]

We eat asbestos for breakfast Rust for lunch Soot for supper

[@aglasserm1679]

@@gordonschweizer5154 Bon Appetit

[@gordonschweizer5154]

@@aglasserm1679 Merci

[@edwier6305]

Should you have raised the height of the vent to 18 inches to avoid the water hammer?

[@gordonschweizer5154]

If the overall steam pressure is kept as low as possible (less than 2 psi), water is unlikely to back up into the horizontal mains and hammer. A tee with the outlet pointed up should be placed 18" back from the vertical drip to avoid water hammer... if this were an ideal situation. But we do the best we can with the situation at hand. Now, with a proper main vent added were there was none, the radiators on the second floor front bedrooms now no longer take over 30 minutes to get hot, but now heat evenly and quietly in less than ten minutes.

[@ga54800]

Could you have tapped directly into the main pipe or return pipe instead of the tee/fittings?

[@gordonschweizer5154]

Yes, we can and have done so in other main vent installations. That is usually when we have better access to the top of the pipe. The cast iron is easier to machine/drill/tap then the steel pipe, and is a bit thicker to allow a few more threads for a tighter seal.

[@JoeSmith-sj4uz]

I have a neighbor who cant find the main vents due to finished basement. Is it possible to install a main at the furthest rad at the end of the main line? Thinking if he had a T added to the riser, gate valve to rad and other side of T he could have a Gorton installed.

[@gordonschweizer5154]

That might work. But I would still advise to open up the areas in the basement at the ends of the mains to make sure you don't have a leaking air vent hidden away.

[@davidlampe4153]

When I felt brave enough to look for the main vent on my system I checked the ends of the mains two mains around the perimeter of the basement, there were two steam traps about 24” before the end of the mains on the dry returns they are the air vents. I also found a Hoffman 75 buried in the ceiling on top of a Hoffman steam separator. This was next to the boiler not at the end of the mains.

[@gordonschweizer5154]

@@davidlampe4153 The two steam traps (likely either the Hoffman #8 or the double-plus- un-good #18) should be either replaced or at least rebuilt if they haven't been attended to this century. They are known as "cross-over" traps and feed the air being pushed out of your mains on a heating cycle back through the dry return to the steam separator. I would replace the Hoffman #75 with a Gorton #2 ASAP.

[@doesntmatter5263]

What type of bits do you use to drill the cast iron?

[@gordonschweizer5154]

As far as their metallurgy, nothing special. Home Despot quality.

[@ga54800]

So do the tap bits not have to be high speed or cobalt when threading? I read regular ones are no good. And what kind of regular and step up bits do you use? Your thoughts?

[@gordonschweizer5154]

@@ga54800 Cast iron has graphite already in it & is easy to machine and doesn't need oil. The taps are ho-hum quality & the step bits are often from Harbor Freight.

[@jackrabbitalex]

That a riser you should have put vent 6" before the ell on the header and raise it 6 to... higher. That gorton gona fail with water. Look up Dan Holohan art of steam.

[@gordonschweizer5154]

When we've had to drill & tap for a main vent, we put it on a shorter riser to reduce the potential stress on the cast iron. What you say will happen simply doesn't in our nearly 20 year experience unless the wet return or pigtail is clogged (then, that's another issue). As to Dan Holohan's steam books, our company (All Steamed Up, Inc), and Steamhead (the person doing the drilling) have been used by Dan as references.

[@ihavethedocuments2580]

If thats not a snap on ratchet you do not know what you are doing.

[@rickstevens6787]

Lucky it didn't crack when you tapped that tee.

[@gordonschweizer5154]

Steamhead has been drilling and tapping tees like this for over twenty years (I'm the one filming). No luck involved: skill, knowledge & proper technique.

[@ihavethedocuments2580]

Naw, he was fine. 👍