#%£*@& No main vents!!

ethicalpaul

I’m buying the big revised book but I thought I’d post for fun in the meantime.

1915 single pipe system. The pipe circuit confuses me but there are for sure no vents except on the rads. They do heat up nicely and apparently quickly enough for my comfort but I’m ignorant!

House built 1915. Originally coal fired (the blueprints have “coal bin” indicated in the basement). 1500 sq ft in a compact 2 storey layout. 8 rads,

Maybe there was a vent on that nipple in the one pic. That spot is what I would call the “end” of the run—the pipe goes down to near the floor and makes about a 5 foot return to the boiler. I can happily answer questions and provide more pics.

I saw a contractor on youtube say the main vent should be some inches away from the bend but my gut says venting this spot would be better than the nothing I have now. Thank you!

neilc

Yeah, you should be able to use that for a vent location,
you should extend that nipple up and out of any "B" dimension(what the boiler pressure pushes back up the wet return)
get your vent up near the ceiling.
1 pipe radiators, correct?
what's your boiler pressure set to? (no higher than 1 1/2, less is better)

ethicalpaul

Thank you. Yes, 1 pipe radiators. Boiler pressure is set at between .5 and 2 on the poorly-graduated setting (see photo). I'm going to get a smaller range pressure gauge so I can make sure it's running where I set it. I have the white differential dial inside set to "1"



OK I can put bends in an extension to get it out of the dimension of the vertical pipe and up higher, I understand what you are saying, thanks!

JUGHNE

A couple of 90 ells with some horizontal pipe will get it above debris and water slugs. The 90's and nipples create "speed bumps" to isolate the vent from attacks.
Position the horizontal such that it maintains the slope of the end of the main. You want any condensate to drain back away from the vent.

It looked like you had 2 mains, if so each needs main venting at the end of the steam pipe. Get the largest main vents you can.

Also, I noticed your pressure control box is used as a junction box. It has happened that wires or wire nuts can interfere with the mechanical operation of controls.
Usually a 4" square J-box is mounted on the jacket and then minimal conductors go into each control. IMO
You might keep this in mind if you revamp any wiring on your boiler.

neilc

I am rethinking my Bdim statement a bit,
I could see a situation where water is pushed up to where the vent nipple comes off the return.
I would think this would not happen until the vent is done venting(boiler wouldn't build pressure enough yet),
if you know your boiler is not above 2#s, (56" above boiler water line)
and the vent is higher than 56" above boiler water level, then you're probably ok,
if you don't have this height then you need to choose a vent that also closes to water (a Big Mouth does not)
Don't loose that cap from that nipple, it's our fall back position.

BobC

It looks like they only used one steam outlet from that boiler and that style of boiler is known to be fussy about the near boiler piping - both side outlets should have been used.

If it's working to your satisfaction just make a note to have the installer of the next boiler do it like the flipping manual tells them.

Bob

ethicalpaul

Oh interesting. There are two large pipes going into the side...I don't see any large exit ports capped off or anything...but I'll go look again. It was installed decades before I bought the place, but when I replace it, I will keep a sharp eye out, for sure.

BobC

What you have is referred to as a Dunkirk style boiler, they sell the castings and people rebadge them as their own.

There should be another steam outlet on the opposite side of that boiler. As I said if it seems to be working oh leave it as is till you need a new boiler.

Bob

ethicalpaul

You were right (you knew that 😄)

Here is the capped outlet. Can you tell me what problems might show themselves from the unused outlet?

ethicalpaul

Here’s my new main vent. I know I might need more but I thought I would start with this. Thanks all!

BobC

If piped improperly that style of boiler can have an unsteady waterline, produce wet steam, and be prone to other ills. Proper near boiler piping is usually very important with that style of boiler.

That new vent is a Gorton #1 (0.33CFM), if that main is short it might be ok but you may need more of them to get the vent rate you need.before doing anything .

Bob

gfrbrookline

You are on the right track. Replace the T with a 90 or put a plug in the unused side instead to the instead of the nipple and cap and turn it so the pipe slopes downward so the vent can drain.

How long are your mains? Measure from the boiler to where you put the vent.

Dan_NJ

I don't see any tape or dope on your threads.

ethicalpaul

I’ll tape them when I fix the T so I can angle it correctly, thanks for the eyes!

I got sidetracked by this 🤣

ethicalpaul

> @BobC said:
> That new vent is a Gorton #1 (0.33CFM), if that main is short it might be ok but you may need more of them to get the vent rate you need.before doing anything .

Thanks, I agree it’s small but I was watching it today and it was barely venting. Is it possible that all my radiators are venting enough that it isn’t seeing much to vent?

gfrbrookline

You want it to look like this.

https://heatinghelp.com/assets/article-images/_resampled/FitWyI2NDAiLCIyNDAiXQ/gorton-vents.JPG

ethicalpaul

The main goes 68 feet around the basement perimeter to get to where I put that vent. It’s about 12 feet from the last radiator branch off the main to the vent. That branch is shown in this photo

gfrbrookline

So based on 1 G2 for every 20' of 2" pipe you need 3 G2's plus your G1 or 1 Big mouth plus one G1 but would likely benefit from a G2 instead since the Big Mouth vents slightly under 3 G2's.

EBEBRATT-Ed

I would boil out the boiler and skim it. Then after running it for a week or so check the ph and adjust

gfrbrookline

You don't want your radiators to do your venting, you want to vent the mains fast and the radiators slowly.

ethicalpaul

> @EBEBRATT-Ed said:
> I would boil out the boiler and skim it. Then after running it for a week or so check the ph and adjust

OK, but what will that do for me? Thanks!

ethicalpaul

> @gfrbrookline said:
> You don't want your radiators to do your venting, you want to vent the mains fast and the radiators slowly.

So like put smaller vents on all the radiators and see if I can force more venting out of the main? Because otherwise I don’t see how I can make any more air vent out of the main. Thank you

ethicalpaul

I put my cut-in basically as low as it would go to get it to cut out at this point (differential is at lowest). Everything leading to the pigtail was all clogged with gunk so I had a chance to clean everything when I replaced the 1/4” nipple that broke when I tried to unscrew it. Not a bad day

gfrbrookline

That depends on what vents you have on your radiators, but take care of the main venting before you tackle the radiators.

To add more main venting you just add more nipples and T's to the antler you started building, ie 90 degree elbow off the riser nipple, 2" nipple, 1/2" T, 2" nipple, 1/2" T, 2" nipple, 1/2" T, 2" nipple the 1/2 * 3/4 90 degree elbow you have the G1 attached to.

gfrbrookline

It should look like this

https://heatinghelp.com/assets/article-images/_resampled/FitWyI2NDAiLCIyNDAiXQ/gorton-vents.JPG

only with 3 G2's and 1 G1.

gfrbrookline

You will also benefit from reading this article by Dan if you haven't already.

https://heatinghelp.com/systems-help-center/balancing-one-pipe-steam-systems/

JUGHNE

Is your 3 PSI gauge protected from the steam with a pigtail of some sort.

I might be late to the party, but the other side of your boiler with the 2"/2 1'2" cap could come off for a skim port.
I had a larger Dunkirk boiler with only one side tap in use, it did work out OK.

If you get the cap off for a skim port you might check inside for the size of the push nipples of boiler sections.
The one I saw had reduced push nipples. Trying to skim with a full port nipple would only draw water out of the closest section.
I added an 1 1/2" reducer to force/raise the skim water above all sections to get even flow from each section. FWIW

ethicalpaul

Thanks Jughne, I understand some of that, and I have the revisited steam book that I'm currently reading so I hope to understand the rest soon. It looks like I'd have to raise the water level quite a bit, like to the high port on the sight glass, to use that port to skim from.

And I don't yet know enough about skimming, like how often to do it in this decades-old boiler, but I plan to learn.

My gauge doesn't have a pigtail in front of it, it just has one after it for the benefit of the Pressuretrol (as seen in https://us.v-cdn.net/5021738/uploads/editor/sx/cctvfhc3k3zj.jpeg )

I again observed the current main vent that I now have during a heating cycle and it did exhaust a nice amount of air. It was never like "whistling" out of there, but rather it was kind of like "puffing" at the beginning of the burn. The main vent closed before the pressure needle even fluttered so even though I'm below the calculated vent capacity for my main line, I feel like there's enough venting there. I sense some eye-rolling maybe at that probably ignorant statement, but I can't imagine what additional venting would do considering the existing vent closes so early.

Here are some fun pictures I found that I thought everyone might enjoy: https://www.gwgillplumbingandheating.com/webapp/p/414/maximizing-vents

ethicalpaul

Got my Big Mouth installed. Didn’t see any noticeable difference from the Gorton #1 but I may when I insulate my mains. Currently it takes quite a while for the steam to get to the main vent due to having to heat all that pipe. I'm going to raise it to the ceiling when I remember to buy a longer nipple.

Here’s my skimming setup on my sadly unused 2nd Utica steam port. It worked great, but I think someone warned me that there may be not a level path inside across sections so it might only be skimming the left one.

gfrbrookline

What vents do your have on your radiators?

ethicalpaul

Maid-o-mists and one variable one

gfrbrookline

What size m-o-m's and what variable vent. I am guessing you are way over venting your rads.

ethicalpaul

Could be since they haven’t been changed (the values, that is) since I added my main vent. I have 4’s on the first floor and 5’s and 6’s on the 2nd floor. The vari one is on one of the downstairs radiators and is pretty much turned all the way down.

What does it mean to be “over-venting my rads?” (I mean, I know what it means, but how would that be bad?)

gfrbrookline

Since your have added venting to your mains you want to slow the radiator venting down. Remember the golden rule "vent the mains quickly and the radiators slowly". You stated it takes quite a while for the steam to get to the main vent. That is because your radiators are still venting your system since they are offering minimal resistance, steam seeks the path of least resistance. You want to fill the main with steam and then have it rise to the radiators so it can evenly heat the building.

You may be able to put 4's on all but your largest radiator or coldest room. Get rid of the Varivent, they are nothing but problems, even set low to off they often still over vent. Replace it with a M-O-M or Gorton. Also make sure you properly insulate your mains, that will make a huge difference in your boiler run time.

ethicalpaul

OK thanks. I agree the variable vent is junky but it makes this fun “clunk” that I’ve grown fond of. I am looking forward to insulating my mains