As mentioned before, I am converting my steam heating system to hot water. I am re-using the radiators, which are Burnham Baseray 9A clones (made by American Standard).

The Basray instructions specify that the supply and return pipes are to feed through the two lower openings (B and E in the diagram) and an air vent is to be installed into the top opening (C in the diagram) of the radiator.

See here: http://www.usboiler.burnham.com/pdf/baseray_spec.pdf

The supply and return pipes aren't too big a deal, that's where the steam pipes fed, and I've been able to remove them, but the vent is becoming a problem.

The opening where the vent should be is plugged, and I cannot get the plug out. I've tried every wrench, vise-grip, pipe-wrench, etc. that I've been able to find, and all any of them do is remove metal from the plug. I've tried using various penetrants to loosen it (Kroil, Liquid Wrench, etc.), all to no avail. The thing might as well be welded in place. I'm reluctant to use a blowtorch to heat it, as I don't want to crack the radiator.

The question is - how vital is that vent? I have an air separator in the loop (Taco Vortech), but it is below the level of the radiators (the Vortech, together with the boiler, is in the basement, the radiators are on the 1st floor). The tops of the radiators definitely form high spots in the loop. Will the air be absorbed by the hot water and brought out to the separator? Or do I really need to get the vents installed?

The only option I've come up with at this point is to drill the plug, thread it for 1/8" NPT, and screw a vent into that, but that seems like a huge PITA to do on every radiator.

Any suggestions?

 

I think venting that air is fairly important. You would end up with expansion tanks throughout the home if the rads were only half full of water.

The air might all go back into the water eventually, but how long is eventually? A long time I think.

Drilling them is certainly an option. I would make that my last hope.

Liquid Wrench is gahbahj. I've not used Kroil so don't know it's abilities... I really like PB Blaster. Smells though... so only use little bits at a time. All you need it to get to is the threads. Be patient and give it time to seep in. A day... add a bit more... another day... give it a chance to do it's magic.

I would try some heat... but certainly not red hot... I'm not sure which would be better, to heat the rad or the plug? Heat will tend to 'grow' the item... Maybe try getting the plug hot, then let it cool before trying... then if that don't work, try evenly heating the area around the plug...

One trick that I learned way back in the day... I was constantly snapping brake bleeders off. Old dude in the shop taught me to crack them loose by TIGHTENING just a wee bit before loosening. I don't know why it works, but it does. Might be worth a try with those plugs...

If all else fails, get out the drill...

 

Heating the plug will expand the plug, making it tighter. Heating the radiator, around the plug, will expand the hole in which the plug is threaded - making it looser.

Intuitively, you might think that the i.d. of hole in a piece of metal would become smaller when heated. It becomes larger.

 

I imagine not having the vent in that baseray will be just like not having a vent in the top of a cast iron radiator. Air trapped in that baseray will not allow it to heat up all the way. You need to water to do the heating, otherwise it's worthless. Plus all that O2 will rust the crap out of your system.

 

This is baseray baseboard. It's not really a radiator in the normal sense of large water volume, open columns, etc. It's just straight tubing inside cast iron mass and fins.

Don't worry about the vents. You don't need them.

Keep the flow rate through the baseboard at 2-4 ft per sec (3-6 gpm in 3/4" pipe) and the air will get back to your air elimination point. Especially if you are pumping away from the expansion tank, which I'm sure you are.

 

But it's NOT baseray... it's American Standard... is it an exact clone?

and, even if it were BaseRay, are you certain that this stuff ain't hollow inside? That the upper ports don't 'communicate' with the lower ports? If there is no communication, then why is a vent recommended on the downstream upper port?

 

The OP should be able to tell, eh? Semantically, the baseray cross-section looks like this:http://www.usboiler.burnham.com/pdf/baseray_io.pdf

 

Without removing it from the wall, it looks just like the pictures of the Baseray. I've been unable to find any documentation from American Standard on this radiator, so I've just been using the Baseray documents. No idea what's inside though - whether it's a single pipe, or chambers, or what.

My current thinking is to skip the venting, get the rest of the system done, and see how t performs. If I get major air problems in the Baseray zones, I'll put in vents in one zone and see if that improves things. If it does, I'll go back and do all of them.

 

I looked through that BaseRay document... and the only 'cutaway' drawing that I saw showed a chamber at the bottom, and one at the top... and it appears that there are 'risers' connecting the two.

I believe that you may not have problems with air blockages... (you might though...) but rather that the heat output will be decreased if the things are only half full of water. And if you pipe in and out on the bottom port, that's what you will have... half to 3/4 full 'expansion tanks' lining your walls.

 

FWIW, I'd go that route, too.