Correct placement for radiator vent?

Tuggy

Hi all,

This is one of 2 radiators in a 19 x 11 ft room living room which is 3rd fl, furthest from the boiler (steam ty@bburd).

It is generally 3-4° cooler than the thermostat setting which is the literally the adjacent room (dining room), 1 floor down.

Putting aside the main run in the basemnt feeding this "line" of the house (which currently has a Gorton No 1), it seems that the radiator vents were placed in the wrong posiitiion on the radiators when installed several years ago, and that the dimple towards the bottom (circled) should've been tapped and the vents placed there.

Is my thinking correct? And this is the reason only alf of the radiator gets hot (above the line) while the rest remains cold?

AND would it make a noticebale difference in temperature in this living room? Cutting that temperature differential a bit?

Thanks

bburd

Assuming this is a steam system rather than hot water, you are correct. The vent should be in the lower dimple you have circled.

Mad Dog_2

Yes, yes, yes! You are on point! Mad Dog

Tuggy

Opinions on whether it is worth the effort to do it? I've never tapped a hole before. Doesn't look too difficult; have the tap/die set.

Will it make a discernable difference in the room temp?

JohnNY

It's already tapped on the other side. You could turn the radiator around and switch the shutoff valve location. The only reason to move the vent at this point would be to get more heat out of the radiator. With the vent where it is, you're depriving the room of 1/3 or so less heat than the radiator is capable of giving you. How do I know? Every thermal image of this condition looks the same. Rather than a big hot rectangle, the radiator shows a huge cool spot or a triangle of warmth and the rest is room temperature.

Tuggy

Do you mean, literally having the shutoff valve at the top, and the vent at the bottom? Essentially switching their positions? That seems like more work, as I'd have to extend the intake pipe up high to the top, no?

ethicalpaul

No, I think he means if you look at the other end of the radiator, you'll see the vent port already threaded there. So disconnect the valve, rotate the radiator 180 degrees and see if that gets you there.

Or maybe the port circled in your picture is already threaded and has a plug in it. But either way, have a look at the other end and see.

Tuggy

I see.

To clarify, BOTH sides of these radiators have these "lower" vent "dimples". I.e., NOT threaded yet, but awaiting to be threaded. (obv not in the picture)

Essentially, each side is exactly the same.

ethicalpaul

ok but check carefully—they may be plugs with slots but just painted over

JUGHNE

IMO, moving the steam inlet valve will be more of a challange than drilling and tapping the 1/8" port.

Tuggy

https://forum.heatinghelp.com/discussion/comment/1744836#Comment_1744836

Yeah, there aren't plugs. These radiators were installed new by plumbers several years ago.

The other side not pictured is exactly the same as what's pictured in the OP.

ChrisJ

Size Q drill bit and an 1/8 NPT tap and you'll have yourself a new hole for the vent.

JohnNY

I've never seen a tube-type radiator that didnt have at least one lower end section's lower vent tapping plugged and ready for use. I believe you that yours doesn't have the threads on one end but then, as mentioned by others, take your time and make your own threads. Or leave it alone and ponder the risk/effort-vs-reward ratio.

Mad Dog_2

1) Tiny steel center punch- 👊 dimple

2) keep bit perfectly sqaure and plumb to hole.

3) WD -40 as you cut

4) Tap pipe tap in to new hole.

5) exert force in to tap as you cut threads. Every few turns back it out a few.

6) Clean off oil and shavings (you don't want the homeowners bare feet to find them...

7) Test your new thread without tape or dope.. Tape & dope new vent in..done

Mad Dog

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745004#Comment_1745004

Personally I no longer do the "back out a few" to break chips. 9 times out of 10 I found it caused problems where just driving a tap home doesn't. Especially in stainless steel. That said, cast iron is also very powdery and never stringy, so I wouldn't back out with that regardless.

Push firmly on the tap until it starts cutting and then just let it do it's thing, it doesn't need pressure after that. Keep going until it's about the depth you want and check the fit with a vent. I like a good 4-6 turns. It ensures a good seal and leaves some meat for later.

Mad Dog_2

You got your way.. I got mine.. never an issue in 40 years- all materials . Mad

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745017#Comment_1745017

That's fine.

But I promise I do far more tapping and thread cutting than you. Probably more per month than you've done in 40 years.

mattmia2

Stainless work hardens so going back and forth makes it harder in both senses.

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745031#Comment_1745031

I've done a lot of tapping in stainless over the past few years..

If I have to tap it, I use a 2 flute plug tap, or if it's a bottom hole I'll start with a plug tap and then switch to a bottom tap that pulls the chips out.

Or form taps work great in aluminum and ok in stainless.

Whenever possible, I thread mill it. Worse case I break the threadmill and it'll just fall out of the hole.

Tuggy

https://forum.heatinghelp.com/discussion/comment/1744994#Comment_1744994

There's a ¾" plug on the opposite side at the top, but neither of the lower vent holes are tapped.

Maybe these (new) radiators were "pre-set" for hot water?

Tuggy

@JohnNY

There's a ¾" plug on the opposite side at the top, but neither of the lower vent holes on either side are tapped.

Maybe these (new) radiators were "pre-set" for hot water?

bburd

@Tuggy if you don't want to mess with it, any good plumber or mechanic can probably tap it for you fairly quickly.

Tuggy

I'm fairly confident I could complete it myself without screwing it up.

I'm just wondering if it would make a noticible difference in the ambient temp in the room to be worth the effort.

There are two of these radiators in this room (19' x 11'), fed by one riser. Each measure 24" x 19" x 5" and are 14 segments. I would need to tap both.

As I said in the OP, the adjacent room gets to 75° where the living room is typically around 72°

bburd

@tuggy you should get considerably more heat out of those radiators, probably enough to get the system into balance.

JohnNY

This is what you got.

Mad Dog_2

Ha ha Chris..then we may be even!! ....sounds like your a Machinist? Thats a great skill. How many boilers you do per month for the last 40 years?? Drilling and tapping is fun but doesn't take but 3 or 4 times to master.....Any simple 1 zone hot water boiler installation with one man being able to size it,, get it down narrow wooden stairs -without doing damage to the home, not losing any fingers or toes, cutting and threading pipe,, soldering, fitting the flue pipe, wiring high & low voltage, oil lines and burner, and then doing a Combustion test takes years of doing everyday, 5 or 6 days a week. Nolo contendre....peace out,...Mad Dog

Tuggy

https://forum.heatinghelp.com/discussion/comment/1744994#Comment_1744994

I have to apologize @JohnNY, you are CORRECT.

There is an allen key plug on one side of these radiators in the lower vent spots.

I suppose I may not have noticed because the radiators, in addition to having the vents in the incorrect upper position, are also not "aligned" in consistent directions-

So on the radiator I pictured in the OP, the lower vent hole on the side where the vent is installed is NOT closed with a plug, requiring tapping.

On the other radiator, the lower vent hole on the side where the vent currently is IS CLOSED WITH A plug.

Now, I wonder which is the better plan for the "mis-aligned" radiator-

Drill and tap it? Or get out the pipe wrenches tape and dope and turn the whole thing around. ?

ethicalpaul

If you have an 1/8" NPT tap I'd probably tap it. If you don't have one, I'd spin it.

Tuggy

I attempted to at least take out the plug from one of the radiators.

I wire cleaned it good first and fit a 3/16 allen socket on a small 1/4 in drive ratchet in there, but the hole started stripping on me so I stopped.

That plug might as well be part of the radiator itself, it aint comin out easily.

Thoughts?

ethicalpaul

Drill and/or EZ Out

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745174#Comment_1745174

Might as well drill and tap the other side.
Be careful with EZ out's in radiators. They like to split the piece and crack things.

mattmia2

Socket drive allen and a hand impact driver for the olther ones. Make sure the allen is a tight fit.

For the future, if you feel it start to cam out turining it with a ratchet, stop.

Tuggy

This is exactly what happened. I was using a sockert drive allen bit on a 1/4 drive ratchet and the plug wasn't moving at all; hole started to strip, so I stopped/

JohnNY

We've been using drill bits, ez-outs, and 1/8" taps on radiator vent tappings for 765 years now without a problem. Well, there was one problem but that was 435 years ago and it's since been resolved amicably. Well, not "amicably" per se, but everyone involved is now dead. Even the ones that survived the initial problem.
Hope this helps.

-JohnNY

ChrisJ

768 years?

That aside there was someone on here very recently that cracked a radiator with an EZ out trying to remove a broken vent.

Ive never had an issue with one my self but I haven't had to use one on a radiator

JohnNY

This was a joke. Not funny? I tried.

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745201#Comment_1745201

It was alright.

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1745201#Comment_1745201

I'm sorry it was a real knee slapper. Funniest I've heard in years!

Tuggy

I noted another member here said for a ⅛" NPT tap to use a size "Q" drill bit.

I'm seeing to use a 21/64" drill bit. Is there some significant difference? (don't think I have a Q)

AND can I just tap directly into that plug if it doesn't come out with an EZ Out? (I'm thinking it probably wont- these radiators were purchased new just like this from the "factory", and those plugs are proly seized in there but good)

mattmia2

you can't tap in to the plug because it is the same size as the hole you are trying to tap. you would have to drill and tap it for 1/4" and use a reducing bushing if you go that route. you can drill a hole that is a bit smaller in the middle and carefully make 2 cuts almost to the threads then break that piece out with a small chisel. there are very thin reciprocating saw blades that can be used to make the cuts in a holder or with tape wrapped around it. you can also try the easy out route.

the hand impact driver will probably remove the ones that aren't sripped.

ChrisJ

21/64 is .3821"

Size Q is .332".

I would see what the manufacturer of the tap you buy says to use. Ive seen some call for size R as well.