Steam distribution help needed - Where is the heat back here

C23_steam

Hello ... I have been using this forum for help already (thank you!!) but want to post on a specific issue as I do not know what direction to head with improving our heat distribution. I have provided as much detail as possible.

Background: We bought a house this summer with a one-pipe steam gas boiler system (two main lines) in New England 1930s small/medium size house. The house was "flipped" with the contractors installing a new gas boiler (Well McLain EG 6), we believe replacing oil, but based on what we can tell did minimal other effort on the heating system. Since turning on the system and hearing bad banging, surging, efficiency, and heat distribution, I have used this forum to help a lot. We have insulated the 2" main pipes, set the thermostat to 1 CPH, flushed and rinsed the boiler 2 times, and installed new main vents (1x Gorton #1 on each ~10' main line) and this had improved the first three issues of banging/surging/efficiency. However we are still having a bad heat distribution problem where essentially the back of the house does not heat.

Issue: Off the boiler there are two main lines (not sure the correct term?), first to the front of the house and second to the back of the house. Off the main to the front of the house there are two radiators on the first floor and two radiators on the second floor which all heat up great (and are the main living rooms/bedrooms so that is good). Off the main to the back of the house there are several radiators coming off in this approximate order: old kitchen which is capped, small bedroom on second floor, old hallway which we have turned off, bathroom on second floor, office on first floor, bathroom on first floor. Although we do hear some air venting during a normal cycle, none of the radiators are receiving any steam/heat! Overall the second main line is colder, I can feel the heat difference when starting up between the two pipes and then that continues as the main vent will vent later than the first/front of house one.

Other notes: We do know steam/heat can get to the radiators, we can get heat if we turn up the thermostat high and wait a long time (60 min?) and we got heat after the two times we flushed the boiler (thinking something about heating colder fresh water?). The air vents on the radiators are old, mostly dole company adjustables, and I plan to change but want to understand more on fixing this issue first. I have never seen our pressure needle go off zero (but maybe I have missed it).

What should I start checking? What can I do to help the heat distribution?

-Thanks in advance!

Jamie Hall

Well... the boiler piping isn't great but it will do. What sort of main vents are there on the two steam mains? That would be the first thing to check. And while you are checking that, check the level of that main to the rear of the house. I'm suspecting that this is a parallel flow system, too, so how does water drain out of the rear main?

109A_5

Hello @C23_steam,
How is the rear main vent doing ? Does it actually vent ?




I'd insulate the radiator run-outs too unless you want the heat in the basement.
I like my old Dole radiator vents, for as old as they are they work good.

C23_steam

I just put on a new Gorton #1 on each of the main vents based on suggestions from this forum, seems to work fine (vents in 30-60 seconds) ... except for as I noted the rear of the house takes longer to get any air venting out.

I would say the rear main pipe level is similar to the front of the house, I dont have a great way to measur, I do see pitching for one of the radiators lines off the main at the end but not really for the others.

Both mains have their own hartford loops on each side of the house which come back together when below the boiler right before going back to the boiler (you can see the T in the last picture).

109A_5

Hello @C23_steam,

C23_steam said:

I just put on a new Gorton #1 on each of the main vents based on suggestions from this forum, seems to work fine (vents in 30-60 seconds) ... except for as I noted the rear of the house takes longer to get any air venting out.

"30-60 seconds" From what ? The start of boiling the the vent closing ?

Since the rear run-outs take off as the main pipe goes along and it looks like the front is all way at the front that may make a difference in your case. Since all the front venting is all at the front of the house, the steam may rush up their faster. The rear fans out more maybe causing the rear main to fill with steam slower.

If you want to experiment some, tape over the vent hole on the front vent and see what changes.
You could also if your are handy take off the rear main vent. Fire up the boiler wait till you see steam coming out of the rear main vent pipe and put the vent back on with protected hands and arms and face. Or just temporary put a full port ball valve where the rear main vent was. See if the back radiators heat faster then.

Ultimately you may need to vent the rear main faster than the front although the mains are about equal length.

C23_steam said:

I have never seen our pressure needle go off zero (but maybe I have missed it).

If you have a 0 - 30 PSI Gauge it may never move. My system is only slightly bigger than yours, my Boiler is 300 Sq. Ft. and the pressure never goes over 1.0 Ounce, usually peaks out at 0.72 Ounces or 1.25 Water Column.

C23_steam

@109A_5 Thanks for the thoughts ... Really interesting point about how the run-outs are different on the back versus the front, I can totally see that it could be adding more resistance in the back.

As for the rear main vent, yea the timing info was unclear on my end its about 30-60 sec for the valve to first have air coming out to it closing. Right now with the two working main vents this takes maybe 5-10 minutes and the rear main vent is maybe 2-3 minutes slower than the front main vent closing (could get accurate timing if that matters). In the process of changing the main vents we actually had an issue changing the front main vent and so for 2-3 weeks we had the front closed off without a vent and only the rear main vent operating. During this time the rear main vent vented and closed faster than it does now and I could feel it heating up faster ... but we still had lots of heat in the front of house and no heat in the back of house. Because of this it feels like the main vents are not the issue for the heat distribution, but interested if you have additional thoughts? Even if I did have more rear main venting would this actually help the steam get to the run-outs and radiators, it seems this is the step the system is struggling with?

109A_5

Hello @C23_steam,
I also wonder, if since your boiler is on the small side the steam simply favors the first main it comes to on the header. A FLIR camera may reveal something interesting. In which case I would would think you would have to slow down all the front venting to help favor the rear. And again I would insulate the radiator run-outs, reheating them each cycle is not helping any. I'd at least partially insulate (near the main) the unused run-outs too.

C23_steam

@109A_5
Yes I think totally possible the front is just favored. Sounds good on additional insulating, that is something I can definitely do myself which I like.

If I really slow down the front venting, I presume that means I will have longer boiler cycles with the benefit hopefully being though that the whole house is getting more heat and takes longer to cool. Any thoughts on what would be a reasonable versus unreasonable time to run the boiler? Ex its a cold day today and with my current just front of house heating I timed the last cycle the boiler turned on for ~30 minutes. As a new home owner still feeling out the balance of $$ efficiency versus heating distribution.

delcrossv

109A_5 said:

Hello @C23_steam,
I also wonder, if since your boiler is on the small side the steam simply favors the first main it comes to on the header. A FLIR camera may reveal something interesting. In which case I would would think you would have to slow down all the front venting to help favor the rear. And again I would insulate the radiator run-outs, reheating them each cycle is not helping any. I'd at least partially insulate (near the main) the unused run-outs too.

I've had to do something similar to this to "time" two feeds so they heated evenly. Probably more extreme than what the OP will need.

SgtMaj

I think your issue is the adjustable radiator vents. Pictures of your radiators including vents and slope of the radiators. I had a customer that had adjustable radiator vents on several radiators, not all and it threw the balance way out. Are all of your radiator valves serviceable? Do they function as required? And why do you have one of your radiator valves closed? And what mfg of main vents did you replace? And did I mention more photos?

guzzinerd

3 traps?  How does this work?

Neild5

guzzinerd said:

3 traps?  How does this work?

They are Big Mouths,  it is a steam trap body that the mfg modified the internals to work as a vent.  They are about the same cost as a #2, but vent about 3x the rate.  

guzzinerd

Neild5 said:

guzzinerd said:

3 traps?  How does this work?

They are Big Mouths,  it is a steam trap body that the mfg modified the internals to work as a vent.  They are about the same cost as a #2, but vent about 3x the rate.  

Interesting, thank you.  Three in a row with triple the vent rate is a heck of a lot of flow.

109A_5

Hello @C23_steam,
Well if you are heating more house that would equal more fuel per hour. If the EDR is reasonable for the heating load and the boiler size (Sq. Ft.) is close to the EDR size boiler run times should be reasonable.

There are many variables, structure insulation, and mine is not the best, etc.

To give one example;
My boiler 300 Sq. Ft. - yours is 258.
I have 9 radiators all working, 347 EDR - you have 8 active ones, EDR unknown.
I have one main pipe about 36 feet long.
Presently my basement is 56 Degrees Fahrenheit.
All basement pipes are insulated except for about 4 feet near the boiler.
At 33 Degrees Fahrenheit outside, my boiler runs for about 7.5 to 8 minutes.
About 36% duty cycle, usually slightly more than two cycles per hour (on-off-on-off).
Old Honeywell T87F Thermostat set at 68 degrees, centrally located on a first floor inside wall.
My boiler is about 50 years old.


@delcrossv I wonder if there is more venting there than the single pipe feeding the three Big Mouths can flow. Although it looks good.


BTW I am presently running a Big Mouth too although presently the output is choked down a bit as an ongoing experiment. I like that I can actually non-destructively take it apart.

109A_5

Hello @C23_steam,
How does the Taco SR503 factor into this whole situation ?
If there is a hydronic loop active when the boiler is steaming the steam output may be diminished.

C23_steam

@guzzinerd Interesting, seems intense

@SgtMaj Radiator air vents are mixture of adjustable dole company 1A perhaps and ventirite adjustable. As far as I can tell they are all working reasonable well but difficult to tell for rear of house because we get so little steam I have little time to check out. The ventirites are on the two bathrooms and office. Overall only pitching issue seems to be for the the first floor bathroom. One of the radiators is closed because it is for an old hallway that is more open concept and the air vent on it broke and I cannot get it off.




@109A_5 There was a hydronic loop setup for a second zone in part of the basement but other than checking once that it kind of works, we never turn it on

Steamhead

@C23_steam , contaminated water can cause this too. Have you flushed and skimmed the boiler?

SgtMaj

@C23_steam while your system is steaming remove one of those vents on a radiator that doesn’t heat to see if you get any air moving. Radiator vents don’t last forever, especially on a system that hasn’t been maintained properly. If a system is balanced correctly you shouldn’t hear air hissing out of a radiator from across a room. Higher pressure will always go to low pressure. The air simply is not moving in the piping on backside of the house. The question is why? Your steam is simply finding the least restrictive path.

You also stated that if you crank the thermostat up and the system runs long enough that the back side of the house heats up, which again reveals that your system is not balanced. Each vent in the radiators depending on the radiator EDR and the size of the room it’s heat loss etc., the vent size was designed into the system to allow a certain amount of air to move at a certain rate to ensure that all the radiators heat up as evenly as possible. It seems to me that the air is moving too fast to the front of the house and the steam/heat is satisfying the thermostat before the air/steam can move through the backside of the house.

So a few questions, how long does it take on a cold start for the thermostat to be satisfied?, and what type of thermostat do you have and where is its location in reference to the radiators on the first floor, and what is the SPAN setting if a digital thermostat, or the heat anticipator if an analog thermostat?

SgtMaj

@C23_steam Here is an example of what I’m mentioning, different sizes of radiator vents based on location/distance of radiators.

109A_5

Hello @C23_steam,
Be careful with the vents. If you break it off (Red arrow) the remainder can be a pain to get out of the radiator. I would just remove the cap and adjuster for maximum flow through the vent, as a test. A coin that fits the slot is all that is usually needed to unscrew the cap.

ChrisJ

@Jamie Hall That's an EG-35 with a 3" riser coming out of it.
What's not great about that piping? It could use some insulation around the entire header, but aside from that I'm thinking it's all that's needed, there's probably no water leaving that boiler at all.

@C23_steam You need to slow the front radiators down some way or another.
Did you show the main venting for the front main? I may have missed it.

You can try slowing that main down, and slowing the 2 radiators down some.
It may take some experimenting, but if it was my house I'd start with putting Gorton #4's, or maybe 5's on the front radiators and then a mixture of Gorton 6's and maybe even C's on the back ones and see how it behaves.

It may take experimenting. You may end up with the back ones overheating etc and you'll need to either increase the front, or decrease the back.

I think MOM has a vent with orifices you can swap out instead of buying a bunch of different vents, but I don't know much about them.

The reason I mentioned slowing the main down is you really want steam to get to the end of both mains at the same time, or very close. If it's shooting to the end of the front main before the rear main even gets steam, that's an issue and very possible. Using a very slow main vent on the front main, or, even totally plugging it may help in this situation.

Those Big Mouths I assume are on the rear main?

You're trying to steer the steam by controlling how fast the air leaves different parts of the system. Right now the front of your system is hogging all the steam, and that's rude. You fix that by slowing those down and letting air out of the rear faster.

JUGHNE

Chrisj, I believe those B&J BM's are on another person's system?

delcrossv

JUGHNE said:

Chrisj, I believe those B&J BM's are on another person's system?

Those are mine to fix the same problem. 3 Big Mouths are the same as an open 3/4 pipe (almost).

ChrisJ

I'm sorry.

That's what I get for scrolling too fast.

JUGHNE

Don't grovel so much, I do that all the time. It makes me go back and analyze whose picture is whose.

It would be nice it there was an easy way to see if pictures were not from the OP.

Maybe big quotes or something like picture in picture.....what do I know, just an old guy.

C23_steam

Hi all, thanks for the thoughts!

I gave it a test with all the front radiator vents on lowest and all the rear radiator vents on highest. I actually got heat out of one of the radiators for the first time on a normal cycle (the one with the first run-out on that rear side) so that is a decent start but no luck with getting heat in the others. Seems like more experimentation in the future is needed with some different radiator vents.

SgtMaj

@C23_steam Do the math and size your vents accordingly and you won’t be disappointed.
https://heatinghelp.com/assets/documents/Balancing-Steam-Systems-Using-a-Vent-Capacity-Chart-1.pdf

109A_5

Hello @C23_steam,

C23_steam said:

One of the radiators is closed because it is for an old hallway that is more open concept and the air vent on it broke and I cannot get it off.

Why don't you repair (as practice) the known broken vent before you have issues with ones that are probably good, possibly causing yourself more grief. I would insulate first before I messed with anything else.

dabrakeman

Just be sure everything is pitched correctly before installing the insulation.