Main vent enough?

MissButters

Hi. We recently moved into an older house (built 1901) that has a mix of cast iron radiators and convectors. We are noticing that the farthest radiator on the 2nd floor from the boiler gets hot, but the room will become cooler than the rest of the rooms upstairs overnight. Also, the convector in the bathroom next to that room does not seem to be working (the pipe does not feel hot to the touch). In another forum, it was suggested we start with the ensuring we have enough venting on the mains. I have attached some pictures of the main vent (we only see one) and the boiler as well as the pressure gauge. Should we put in a bigger vent or add a vent somewhere?

Fred

You have two mains. Each should be vented. That one vent, in your picture is a Gorton #1. Probably not nearly enough venting capacity. How long is each Main? Where is the return for that second Main?

New England SteamWorks

Just a guess from the pictures, but it looks like you have one counter flow main, and one parallel flow main. The counter flow main should have it's vent at the end of the main, and the parallel flow main vent (pictured) is too small.

But having said that, I don't see a drip for the counter flow, nor do I see a second return should it not be counter flow.

Fred

Isn't there usually a drip on the main somewhere near the boiler on a Counterflow @New England SteamWorks ? I see what I think is a wet return on the floor, behind the boiler that is coming from the direction of that front main. I'm wondering if that main is also a parallel flow but the return drops to the floor at the end of the main???

New England SteamWorks

neilc

looks like the top of the water heater gas main.
Do not vent that.

Dave0176

Fred said:

Isn't there usually a drip on the main somewhere near the boiler on a Counterflow @New England SteamWorks ? I see what I think is a wet return on the floor, behind the boiler that is coming from the direction of that front main. I'm wondering if that main is also a parallel flow but the return drops to the floor at the end of the main???

That’s kinda what it appeared to me too @Fred but it’s dark and can’t really tell.

Also @MissButters your pressure is set too high, that should be down to .05 and inside the wheel should be 1.

Fred

Looks like the gas linethat drops down to the water heater to me, with a Tee and a plug in it.

FinishGuy

I might have spotted the other end of the second main.

Fred

I think you are right @FinishGuy . If @MissButters can confirm that that pipe drops to the floor and runs over to a pipe that runs into the boiler, then that's where another vent needs to be installed.

EBEBRATT-Ed

I am goin with @FinishGuy , I think there both parallel supply return and that tee drops to a wet return the one that runs behind the boiler.

Not a fan of "gastite"
But I am so excited

The installer did the header right!!!

FinishGuy

Looking at the original posted photo, I think the shadow of a vent is visible.

There is also this.

nicholas bonham-carter

I’m wishing Miss Butters well, and hope she has not become so confused with an inundation of information that she has given up on improving her system!—NBC

FinishGuy

I hope @MissButters does return. It would be nice to hear how her travails are working out, but something else has caught my eye.

Miss, I am a finish carpenter by trade. I have done some framing though, mostly by way of working for others over the years. Something is amiss with the built-up beam in your photos and your basement.

I suspect the old carrying beam was strengthened by sistering a new piece of 2x lumber along its length on both sides, most likely nailed and lag bolts used, the heads of which can be seen.

The 2x on the flat, on the bottom, has moved down and away from this built-up beam. I am uncertain about what purpose it served. As currently constructed perhaps it was meant to prevent twisting of the new assembly? It never provided much in terms of weight bearing ability to the built-up beam.

The concern is that it might fall off. It looks to be a goodly length and therefore heavy and likely to hurt would it hit someone. It may have been like this for decades or maybe not.

Please have a carpenter look at this. If it is indeed an integral part of the beam it can be jacked up and securely attached. Just not with nails going straight up and no adhesive.

Fred

@FinishGuy , it actually looks like the flat board is, it actually looks like the flat board, on the bottom may be securely nailed to the old timbers and that they may have sistered new 2X6's along side maybe 2X8's. Not sure why they even bothered with the flat board on the bottom, unless they were trying to hide some termite damage or other damage.

MissButters

FinishGuy said:

I might have spotted the other end of the second main.

So, I did go and verify that it looks like it is two parallel flows, and the pipe does drop to the floor behind the furnace. Are we missing a vent on what is labeled Main B? We did put a bigger vent on Main A. Would not having a vent on Main B cause the convectors that it goes to first make large hissing noises?
Thanks!

nicholas bonham-carter

Missing or inadequate main vents will make the radiator vents hiss, and make the system unbalanced, with some radiators getting steam long before others.
It’s not enough to have a small vent on each, and think you are done, as you will be burning extra fuel to squeeeeeze the air out of constipated little openings.
Put a low pressure gauge on, and add vents until the air escapes at less that 2 ounces, as steam begins to rise.—NBC

ethicalpaul

You all know I hate to make a counterpoint haha but I daresay the Gorton #1 is big enough in this situation as it is.

This is because with uninsulated main pipes, the steam does not move fast on cycle start. It has to heat the pipes and it condenses as it goes making for a very slow advance.

I’ve been monitoring my uninsulated main with my hand and monitoring my Gorton #1’s performance during many heating cycles over the last 2 heating seasons. The only time I can even feel more than a whisper of airflow from the vent is when the steam is progressing down the last 7 feet of 1-1/4 pipe between the last radiator takeoff and the vent. That is 5 seconds out of the 7-8 minutes it takes from first steam generation to steam hitting the vent.

I hope to require more venting when I finally install my insulation.

Back to this case, definitely vent the unvented main but don’t panic about the existing vent until/if/when the main is insulated. My 2¢

Fred

This is a two year old post. Not sure MissButters is listening anymore.

Hap_Hazzard

Fred said:

This is a two year old post. Not sure MissButters is listening anymore.

It looks like she got up and posted at quarter to eight this morning. ¯\_(ツ)_/¯

Fred

Wow, @Hap_Hazzard , you are right!

Hap_Hazzard

Fred said:

Wow, @Hap_Hazzard , you are right!

It happens.

ethicalpaul

Autumn brings people to Strictly Steam!

MissButters

We put a Gorton #1 (cause that's what we have at the moment) on the Main B vent that seemed to be missing. I'm curious if it is going to help some of the convectors not hiss as much and if it helps one of our radiators towards the end of the line get warm. Thanks everyone!

ethicalpaul

It will definitely be better than no vent. Did you lower your pressuretrol to .5 psi as suggested earlier? That will reduce hissing and save wasted fuel too

gfrbrookline

I would add a Barnes and Jones Big Mouth to each main. They are the same price as one Gorton No.2 and vent almost three times as fast. The more main venting you have the less you will hear the radiator vents. Just put them on a 10 to 12" nipple if possible since having any vent on the drop down 90 is not ideal.
They should be installed at least 18" before the drop.

Have you insulated your mains? That will also make a huge difference in steam distribution.

MissButters

Unfortunately, I don't think we have the clearance to put them up 10-12", but I'll check when I get home. We have not lowered the pressuretrol to .5 (silly question - is that the slide switch)? I think one of the mains is insulated, but the other is not. Lastly, would not venting the main enough cause one radiator at the end of the line to not get completely hot? We noticed our office on the side off Main B is cool and the radiator only has the first half of the sections get warm. Thanks again!

Jamie Hall

@MissButters , I'm with @ethicalpaul on this one. Not that there is such a thing as overventing a system -- there really isn't -- but there is such a thing as enough venting, and in my humble opinion you are just fine with that #1 on that main (Cedric, the dragon in the main place I care for, is vented with 1 Gorton #2 and a Hoffman #76 -- for almost 200 feet of 3 inch main. And it's ample). As several have mentioned, though, insulation of the mains is really important.

MissButters

Thanks again. For the insulation, do we start insulating the mains starting at the vertical pipe off the header, or wait till the next horizontal pipe?

ethicalpaul

MissButters said:

We have not lowered the pressuretrol to .5 (silly question - is that the slide switch)?

It's not a slide switch, it's just an indicator. You move it up and down with the screw at the top of the device. But you, or whoever is doing it should have some sense of what they are doing. There is also a dial inside the device that should be checked.

You or whoever does this should have some sense of electricity and general "handiness". You should get the book "we've got steam heat" from this site's store if you want to learn, and you can learn a lot from this forum, but there is a lot of information coming at you so it can be a little overwhelming.

Jamie Hall

MissButters said:

Thanks again. For the insulation, do we start insulating the mains starting at the vertical pipe off the header, or wait till the next horizontal pipe?

Everything that carries steam, except radiator runouts in living spaces (or hidden in walls!).

MissButters

ethicalpaul said:

MissButters said:

We have not lowered the pressuretrol to .5 (silly question - is that the slide switch)?

It's not a slide switch, it's just an indicator. You move it up and down with the screw at the top of the device. But you, or whoever is doing it should have some sense of what they are doing. There is also a dial inside the device that should be checked.

You or whoever does this should have some sense of electricity and general "handiness". You should get the book "we've got steam heat" from this site's store if you want to learn, and you can learn a lot from this forum, but there is a lot of information coming at you so it can be a little overwhelming.

Thanks! Book has been ordered through this site!

nicholas bonham-carter

If you were lucky enough to have a two-pipe system you could have relatively small main vents, because the venting is serial; whereas a parallel flow one-pipe system is vented in parallel with the radiator vents, and so needs more capacity.
Putting more main venting on will reduce the hissing of the radiator vents, and make sure all radiators receive steam at the same time.
One Gorton #2 is good for 20 feet of 2 inch main.
Having a low pressure, verified by a gauge calibrated in ounces will help as well.—NBC