Steam Radiator Vents

CKNJ

I am baffled by this one. 1909 One pipe system, dry return, new pigtail, new pressuretrol (Set 1/2 cut in; 1 cut out), new pressure gauge. Mains have "Big Mouth" vents and work perfectly (Thank you Wall members). Main vents in no time flat.

Living Room has 2 radiators (one 7 section and on 9 section), 2" main and 1 1/4" line to radiator. All lines insulated with 1" pipe insulation. On the first floor, I had Hoffman 40 vents on all radiators and they worked fine. I wanted to increase heat to living room as it is a large room and the rest of the floor gets too warm. So i put Gorton #5 valves on both living room radiators. Well, both radiators (2 different supply lines) get fully (all sections) hot and start venting steam mixed with some droplets of water. I thought maybe i had bad valves so I bought another one. Same thing happened. I removed the valve, turned upside down and blew into it. It closed. Put it back and same thing, fully heated up and still allowing steam and some spitting water (just droplets). I put the Hoffman 40 back on and it shuts off perfectly. I check my pressure gauge (1 to 15 lbs range) and it doesn't move so i don't think it is pressure related. I really want to have the living room heat up faster but it doesn't look like this is possible.

What am i missing? Is it possible the bigger valve is allowing too high a steam velocity and keeping valve from closing?

Jamie Hall

If the steam is getting to the vents in a reasonable time, you're getting all the heat from the radiators you are going to get. The real question is, do they heat to the point of vent closing sooner or slower than the other radiators?

Fred

Check the pitch on those radiators. If they are level or pitched the wrong direction, enough water can pool in them for the steam to carry some of it up into those vents. Didn't happen with the 40's because that is a slow vent, keeping any internal velocity/disturbance to a minimum. You may also want to try an adjustable vent like the Hoffman 1A or the Vent-rite so that you can play with the venting a bit.

RomanGK_26986764589

Seems like Gortons aren't that reliable anymore as they once were. I also had put new Gorton vents on my rads and they all leaked steam. I've replaced them all with Maid O Mist vents and they work much better.

CKNJ

I checked the pitch on the radiators and it is fine. Pitched back toward the supply valve, so no issue there.

CKNJ

Jamie Hall: The issue is that I have Gorton #4 on bedrooms and bathroom on 2nd floor. I am ending up with a 5 degree temperature difference between floors. My thought was to increase venting to living room to heat faster, matching the rest of the first floor (dining room and kitchen are closer to boiler and heat up faster) and keeping the temp on 2nd floor down. Example with all 40's on first floor and 4's on second, the temp on first floor is 68 and 2nd floor is 75.

Fred

Put the #40's or adjustable vents back on the first floor and on the second floor and adjust each one as needed.

Danny Scully

Are they recessed cast iron radiators?

CKNJ

Danny: Nope, freestanding 3 column cast iron 37" tall.

Jamie Hall

CKNJ said:

Jamie Hall: The issue is that I have Gorton #4 on bedrooms and bathroom on 2nd floor. I am ending up with a 5 degree temperature difference between floors. My thought was to increase venting to living room to heat faster, matching the rest of the first floor (dining room and kitchen are closer to boiler and heat up faster) and keeping the temp on 2nd floor down. Example with all 40's on first floor and 4's on second, the temp on first floor is 68 and 2nd floor is 75.

Venting is a balancing act. The first thing, of course, is the main venting -- that has to be completely adequate. Then if that is really adequate, one can start playing with the radiator vents -- and it sounds somewhat backwards, but often it works better to slow down the radiators which heat faster than you would like rather than to try to speed up other radiators to match. This may be where you are. That said, you might try significantly slower vents on the second floor and see what happens.

BobC

The Ventrite adjustable vents have the lowest vent rate I know of. Gerry Gill's chart shows it having a venting rate of 0.025 at setting #2 vs the Hoffman 40's 0,040. Does anyone know if the .025 at setting 2 and 0.03 at settings 1 and 3 are consistent or was that just an anomaly?

If you want slower you would have to take the maid o mist vent and replace the normal orifice and replace it with a plug that you drill out with a #60 drill bit or something like that but first we have to figure out what the orifice plug thread is.

CKNJ

Jamie: Main is 2" pipe with a Gorton #1 Main Vent and a B&J Bigmouth. That main vents very, very fast.

I think for now I will put the 40's back on those 2 radiators and make adjustments to the 2nd floor radiators to "slow" them down.

Thanks for everyone's help here. Really appreciate the help.

Chris

CKNJ

Just as a point of reference, it takes less than 3 minutes for steam to reach the end of the 22 foot main. I think that is pretty good.

Jamie Hall

Sounds like your good on the main vents -- I just wanted to be sure! Now it's a matter of playing with the radiators... takes patience and time, and remember that changing one affects all the others. You'll get there!

CKNJ

Just wanted to follow up on my original post. Just to make things a little stranger a couple of days after my last post it seems the system "calmed down". The 2 problem radiators no longer spit, heat up nicely and the temperature difference is only 2 degrees between floors. I didn't make any adjustments or change valves! Not going to complain as long as it works.