4 of 8 rads in one pipe system not heating, help please.

tjohnson2342

Hello everyone, I’ve been lurking on this forum for a while now and hoping that someone can give me some good advice on my steam system.

System Specs:
New England house built in 1947, 1100 sq ft with a one pipe steam system. 8 total radiators in the house, 4 upstairs and 4 downstairs. My wife and I just purchased the house last year and the old oil fired boiler **** the bed twice during February (25 year old unit), so we decided to upgrade our boiler this past spring. Before gas prices and inflation exploded we decided to convert to gas and have a new gas boiler installed. Instal completed in October 2021. Fast forward to today, we have begun to notice that half of our radiators do not get hot… at all. All 4 radiators that are branching up from the basement on the end of the loop are not getting hot at all.

We called our heating guy who by all accounts appears to be pretty well versed on steam systems, (i'm no expert but after this whole process im beginning to learn). He said that because the pipes in the basement are not insulated it's possible that when we start a heating cycle the steam is condensing before reaching the end of the loop, thus those radiators not heating up. It sounds logical but then when we run the system I can hear the vents on those cold radiators hissing, but no heat. His recommendation was to just run the heat, set the temp to whatever we like and just let it run so that hopefully that pipe does not get very cold. Also insulating the pipes wouldn't be a bad idea. I was not super thrilled with his solution.

However, through our first winter in this house, those pipes were not insulated, with an old boiler that crapped out twice towards the end, but we did not have an issue of radiators not getting warm when the boiler was working. So while I’m no expert I have trouble believing him. Since we had one season where we saw those radiators heat up and now we have a new boiler installed and they do not.

I’m hoping someone can give me some useful advice or even recommend someone in CT ideally. I’ve used the find a contractor tool on this site leading me to only 1 person in Massachusetts who I reached out to but never heard back from. I’m willing to answer any questions anyone has that might help further diagnose the problem. Here are some photos of everything.

-Thanks

neilc

if it's 4 rads at the end of that main loop,
I would suspect the main vent, which I can't get a good look at,
if it's too small maybe all the air isn't getting out before the thermostat rad satisfies,
more main vent, and slower rad vent(s) at thermostat and any hot rooms,
picture of main vent, and if you can make out its name and size,

cross_skier

Vent the heck out of the mains, insulate them and that should fix the problem.

EBEBRATT-Ed

In addition to the above posts about venting

Try keeping the water level in the boiler at 1/2 glass full. If it's a little low now you could be tripping the low water cutoff when running and interrupting the steam production.

Watch the water level in the boiler when it is steaming. How much does it bounce? an 1" or so isn't bad more than that is wet steam.

Was the boiler cleaned and skimmed after install.

Where in Ct are you located?

mattmia2

Is tat one vent by the boiler the only vent on the main? Was the old boiler connected the way this is with the supply at one and and the return at the other end of the main?

BobC

That looks like a good install job but it's possible the main got moved during the work. It looks like parallel flow so the steam main should be high where it gets it's feed from the boiler and slowly slope down as it winds it's way around your basement. How long is the steam main and about what size pipe is it? Start the boiler when the system has been off for a few hours and feel along that main to see how fast the steam is moving along it.

I can just see the bottom of what looks like a main vent and it looks like a hoffman 4A which at 0.133cfm may be to slow. I'd use a much larger vent (Gorton or maid o mist #1 is 0.33cfm and a Gorton #2 is 1.1cfm), that #2 is a large vent so make sure you have the height for it. I'd insulate the near boiler piping and the steam main.

Bob

Jamie Hall

Certainly part of your problem is no insulation on the mains.

But -- is that the end of the main which I see coming along, turning towards the wall, and then dropping down to the return? And if so, is that a vent on the small diameter riser very near the end?

How far along the main do you sense heat when the boiler runs? If I'm seeing what I think I'm seeing, it should get hot right up to that little vent, though it may take a while.

I'm a little concerned, too, that there seems to be relatively little elevation difference between what I take to be the end of the steam main there and the beginning of it, over the boiler. Is it possible that there is a sag in it somewhere?

Would kindly go along the full length of the main -- from the boiler all the way back to where it drops -- and see how far along it gets hot, and how long it takes? That will help a lot.

tjohnson2342

https://www.reddit.com/user/mr_robot2369/comments/rj9q63/boiler_cycle/?utm_source=share&utm_medium=ios_app&utm_name=iossmf


EBEBRATT-Ed-
I’m very new to this all so I sat and watched the boiler in the middle of a heating cycle and linked in a 3 minute clip of the sightglass during a cycle. Low water level was tripped 3 times just in 6 minutes which to me seems wrong. I don’t know what I’m supposed to be looking for but I didn’t like the look of that foamy water coming in from the top of the sightglass, maybe it's normal but I don’t know enough. How steady should the water level remain during a heating cycle in that sight glass? At some point the low water will trip and the boiler will stop, sight glass will fill back and start over again but how much is too much, how stable should that water level be throughout the cycle? To answer your question, yes the boiler was skimmed, cleaned and conditioned after install. I am in Hartford County in CT. You would think with the amount of old homes in my area there would be some more “steam experts' ' around, I know it’s a dying breed or maybe I just haven't been able to find them yet. But it has been difficult finding someone who knows what they’re talking about, even more so when I have no idea either other than gut instinct when one of these guys is feeding me ****.

BobC-
When you say main, I am assuming you mean the main loop of pipe around my basement immediately exiting and returning to my boiler? If so then the main pipe is 1.8” all around the basement. With some larger and smaller piping immediately around the boiler. When the system has been off for a while and we call for heat, it only takes about 10-15 minutes for those pipes to get hot, and they seem to be the same temp at the start of the loop, the middle and the end of the loop. Which is why I'm so confused that the piping in the basement directly below one of the cold radiators is extremely hot, yet the rad is cold and even the air hissing out of the vent at the rad is cold.
If the main vent you are referring to is the one that's jutting up towards the floor joists in the ceiling then it is a No. 75 Vent-Rite.

Jaimie Hall-
Yes the end of the main is on the left in those pictures and the beginning is on the right, there is an elevation difference (not sure if it's enough) I think the angle of the pic makes them appear more even then they are. I’ve felt heat on the main pipes downstairs around the entire loop, they seem to be the same temp at the beginning and end but that is not being reflected in the steam making it to the radiators. Generally it takes 10-15 minutes for those pipes to get hot to the touch.

Question: Everyone seems to agree that insulation, while maybe not solving the issue entirely, is a good step in the right direction? I’ve done some googling and many seem to suggest fiberglass pipe insulation with the slit on one side and to not use the insulation tape. Is this what you would recommend? How snug of a fit around the pipe does it need to be? (I bought a piece of 2” fiberglass pipe insulation and it was pretty loose due to the piping being 1.8ish”, should it be a tight fit? Also how close to the boiler can i get with the insulation, should I just insulate every exposed piece of piping that I can get to?

Apologies for the extremely long post and replies, but I really do appreciate everyone's insight on this.

mattmia2

The radiator isnt heating because the boiler is either priming or surging and throwing water in the mains and that is blocking steam to that radiator. Because it only has one riser connected it will be more sensitive to water quality issues in the boiler. That boiler probably shows the second riser as optional but with 2 it slows the steam down because there is more vertical area and gives the water more opportunity to fall in to the boiler and the steam can get out of both ends instead of all having to travel to one end of the heat exchanger. Is there a water treatment in the boiler, it may be causing the water to foam. If so drain and refill the boiler and fire it until it steams to drive the oxygen out of the fresh water. You aren't using softened water are you? May need to skim again but it sounds like priming(foam carrying water with the steam) rather than surging(steam violently erupting from the surface of the water because there is a film of oil on it).

The water level should vary very little while it is steaming

Jamie Hall

Agree with @mattmia2 -- what, if anything, are you using for water treatment? The water level should be pretty steady -- anything much more than an inch up and down is too much. That much bouncing and the presence of foam points to a water quality issue (among other things...).

Therefore, as he said, drain the boiler completely (when it's at least cool!) and refill with ordinary tap water -- not softened water -- and bring it up to steaming.

If that main gets hot at both ends, then at least it's not being blocked by a say somewhere. 10 to 15 minutes is a bit long for steam to get around, but that's at least as much due to lack of insulation as anything else. A pipe outside diameter of 1.8 inches sounds like 1 1/2 inch ductile iron pipe, and that is the size insulation which you should use -- and yes, the fiberglass with a slit in the side is the right kind. Bring it as close to the boiler as you can.

The existing vent is probably a bit small, though it's a very good vent.

I don't think we've ever found out -- how are the 4 radiators which don't get hot related to each other and to the radiators which do?

As to steam experts, your best be in the Hartford area of CT is going to be @Charlie from wmass -- who was, when last heard from, absolutely swamped with work. There's no harm to sending him a PM, though.

Hap_Hazzard

Am I crazy, or is one main branch piped up from the return?

Or does the main we see exiting above the louvered door come back around? If that's the case, isn't it a problem that it seems to be reduced down to 1½" or 1¼" before it even leaves the boiler room?

I can't be sure from these pictures, but what I'm seeing looks like it was originally intended to be two counterflow mains, not opposite ends of a circular main. It would certainly explain why they're not getting any heat from one branch.

tjohnson2342

Jamie Hall said:

Agree with @mattmia2 -- what, if anything, are you using for water treatment? The water level should be pretty steady -- anything much more than an inch up and down is too much. That much bouncing and the presence of foam points to a water quality issue (among other things...).

Therefore, as he said, drain the boiler completely (when it's at least cool!) and refill with ordinary tap water -- not softened water -- and bring it up to steaming.

If that main gets hot at both ends, then at least it's not being blocked by a say somewhere. 10 to 15 minutes is a bit long for steam to get around, but that's at least as much due to lack of insulation as anything else. A pipe outside diameter of 1.8 inches sounds like 1 1/2 inch ductile iron pipe, and that is the size insulation which you should use -- and yes, the fiberglass with a slit in the side is the right kind. Bring it as close to the boiler as you can.

The existing vent is probably a bit small, though it's a very good vent.

I don't think we've ever found out -- how are the 4 radiators which don't get hot related to each other and to the radiators which do?

As to steam experts, your best be in the Hartford area of CT is going to be @Charlie from wmass -- who was, when last heard from, absolutely swamped with work. There's no harm to sending him a PM, though.

I am not sure at all about water treatment being used to be honest and I’m not exactly sure how I can drain the boiler and then add in tap water. I’m not sure if I would trust myself to perform that kind of maintenance without a pro.

I did some research on nominal pipe sizes and found out that 1.5” pipe is what I have thank you for confirming this. Also confirmed this by running out to home depot and grabbing a section of fiberglass insulation for 1.5” pipe and it fits nice and snug. A fix that I feel confident performing at least is insulating all exposed piping that I can get at. I plan on placing a larger order to grab enough of that pipe insulation. Should I only concern myself with the piping original to the house on the main or also insulate any exposed piping all around the boiler? Meaning all that darker black piping vs the clearly older piping that was original to the house?

As far as the 4 cold rads and how they’re related to each other. All 4 rads are on the front wall of the house, 2 downstairs and 2 upstairs. That front wall is the end of the main loop and the 2 upstairs rads are essentially stacked on top of the 2 downstairs rads so I would imagine they all share piping there but obviously cannot confirm that without ripping open walls.

Charlie from wmass is who I sent an email to a few weeks back and never received a response, I assume because of being busy but I will take your advice and send a pm through here.

tjohnson2342

Hap_Hazzard said:

Am I crazy, or is one main branch piped up from the return?

Or does the main we see exiting above the louvered door come back around? If that's the case, isn't it a problem that it seems to be reduced down to 1½" or 1¼" before it even leaves the boiler room?

I can't be sure from these pictures, but what I'm seeing looks like it was originally intended to be two counterflow mains, not opposite ends of a circular main. It would certainly explain why they're not getting any heat from one branch.

Yes the main you see exiting the louvered door loops all around the basement and then returns back to the boiler on the opposite side.

dopey27177

Many comments were made all good.
Here is my take on the system.
Install a Gorton or Maidomist # 1 vent valve on the return where the small vent valve is located.

As important, insulate the steam main, that will save fuel and change the way the system operates, all for the better.

Jake

tjohnson2342

tjohnson2342 said:

Jamie Hall said:

Agree with @mattmia2 -- what, if anything, are you using for water treatment? The water level should be pretty steady -- anything much more than an inch up and down is too much. That much bouncing and the presence of foam points to a water quality issue (among other things...).

Therefore, as he said, drain the boiler completely (when it's at least cool!) and refill with ordinary tap water -- not softened water -- and bring it up to steaming.

If that main gets hot at both ends, then at least it's not being blocked by a say somewhere. 10 to 15 minutes is a bit long for steam to get around, but that's at least as much due to lack of insulation as anything else. A pipe outside diameter of 1.8 inches sounds like 1 1/2 inch ductile iron pipe, and that is the size insulation which you should use -- and yes, the fiberglass with a slit in the side is the right kind. Bring it as close to the boiler as you can.

The existing vent is probably a bit small, though it's a very good vent.

I don't think we've ever found out -- how are the 4 radiators which don't get hot related to each other and to the radiators which do?

As to steam experts, your best be in the Hartford area of CT is going to be @Charlie from wmass -- who was, when last heard from, absolutely swamped with work. There's no harm to sending him a PM, though.

Also quick question on thickness of insulation, I believe the 3ft piece I grabbed from Home Depot to confirm the size I need is 0.5" thickness insulation. Is there any standard I should use for thickness? Any max or min thickness to provide the best results?

Charlie from wmass

1 inch minimum wall thickness. Home Depot is a waste of time and money. Online or local Plumbing Supply like Benders. 

Hap_Hazzard

tjohnson2342 said:

Yes the main you see exiting the louvered door loops all around the basement and then returns back to the boiler on the opposite side.

So the part of the main I can see is reduced down to 1½" or 1¼" before it leaves the room. Is that it, or does it get even smaller where I can't see it?

tjohnson2342

Hap_Hazzard said:

tjohnson2342 said:

Yes the main you see exiting the louvered door loops all around the basement and then returns back to the boiler on the opposite side.

So the part of the main I can see is reduced down to 1½" or 1¼" before it leaves the room. Is that it, or does it get even smaller where I can't see it?

1.5" is the smallest it gets.

Jamie Hall

Do the risers for those two stacks of misbehaving radiators rise vertically, or at least at no less than 45 degrees from vertical, from the main? Is there any horizontal runout to where they go vertically upstairs? I'm wondering if they might not be trapping water if the main in that area had been raised when the new boiler was installed.

tjohnson2342

Jamie Hall said:

Do the risers for those two stacks of misbehaving radiators rise vertically, or at least at no less than 45 degrees from vertical, from the main? Is there any horizontal runout to where they go vertically upstairs? I'm wondering if they might not be trapping water if the main in that area had been raised when the new boiler was installed.

I am not exactly sure if there is any horizontal runout, not exactly sure what I would be looking for there. I've attached 2 photos of where one of the problem radiators is located at the end of the main and the pipe going up to that.

tjohnson2342

Charlie from wmass said:

1 inch minimum wall thickness. Home Depot is a waste of time and money. Online or local Plumbing Supply like Benders. 

thank you! I plan on measuring out what I need and making a larger order online.

tjohnson2342

mattmia2 said:

The radiator isnt heating because the boiler is either priming or surging and throwing water in the mains and that is blocking steam to that radiator. Because it only has one riser connected it will be more sensitive to water quality issues in the boiler. That boiler probably shows the second riser as optional but with 2 it slows the steam down because there is more vertical area and gives the water more opportunity to fall in to the boiler and the steam can get out of both ends instead of all having to travel to one end of the heat exchanger. Is there a water treatment in the boiler, it may be causing the water to foam. If so drain and refill the boiler and fire it until it steams to drive the oxygen out of the fresh water. You aren't using softened water are you? May need to skim again but it sounds like priming(foam carrying water with the steam) rather than surging(steam violently erupting from the surface of the water because there is a film of oil on it). The water level should vary very little while it is steaming

I do not believe we are using softened water, we have city water. I just drained the boiler and my automatic feeder filled up the sight glass up to where you can see in the photo. 

mattmia2

Is the water line more stable while steaming now?

Steamhead

@tjohnson2342 , how long is that steam main, between the boiler and the main vent?

dabrakeman

Replace that main vent with at least a Gorton #2. That Ventrite 75 is equal to just a medium flow radiator vent. Then insulate as you are planning. Both should be done anyway with a likely chance of fixing your issue. If your downstream problem radiators are still blowing cold air while others upstream are hot then it really seems like main venting. Steam takes path of least resistance.

tjohnson2342

Steamhead said:

@tjohnson2342 , how long is that steam main, between the boiler and the main vent?

Roughly a 60 ft loop around the basement 

tjohnson2342

dabrakeman said:

Replace that main vent with at least a Gorton #2. That Ventrite 75 is equal to just a medium flow radiator vent. Then insulate as you are planning. Both should be done anyway with a likely chance of fixing your issue. If your downstream problem radiators are still blowing cold air while others upstream are hot then it really seems like main venting. Steam takes path of least resistance.

https://www.supplyhouse.com/Gorton-G2-Gorton-No-2-Straight-Air-Eliminator-3524000-p

This?

Steamhead

tjohnson2342 said:

https://www.supplyhouse.com/Gorton-G2-Gorton-No-2-Straight-Air-Eliminator-3524000-p

This?

Yup. For that long a main, the #2 is what I'd use.

tjohnson2342

mattmia2 said:

Is the water line more stable while steaming now?

Just watched it this morning at the beginning of a cycle and it does not seem to be more stable. Sat down for about 5 minutes and it bounced around and then hit low water level and shut off. Turned back on, watched for another 5 minutes and same thing, water level fluctuates for a bit more of that foam dripping from the top and then hits low water level and shuts down again. 

dabrakeman

The #2 has 10x the venting capacity of your Ventrite 75. I know it seems expensive but it also has 3x the venting capacity of the less expensive Gorton #1. Get 3 Gorton #1's and it is about the same. I ahve found the Gorton #2 to be a very reliable valve. You can add on your existing Ventrite 75 if you put the vents on an antler but the Ventrite won't add much. (I did on mine just because I hated to waste a functional vent regardless how small...).

Have you traced how far around the main your steam gets when the boiler first shuts off from the lwco? Make sure you are tracing the steam advance, steam hot not just condensate hot (start near the boiler when pipes still cold and wait for the rapid heat up of the pipe which indicatesthe arrival of steam and then move down the line to a new cold section of main and repeat...

tjohnson2342

dabrakeman said:

The #2 has 10x the venting capacity of your Ventrite 75. I know it seems expensive but it also has 3x the venting capacity of the less expensive Gorton #1. Get 3 Gorton #1's and it is about the same. I ahve found the Gorton #2 to be a very reliable valve. You can add on your existing Ventrite 75 if you put the vents on an antler but the Ventrite won't add much. (I did on mine just because I hated to waste a functional vent regardless how small...). Have you traced how far around the main your steam gets when the boiler first shuts off from the lwco? Make sure you are tracing the steam advance, steam hot not just condensate hot (start near the boiler when pipes still cold and wait for the rapid heat up of the pipe which indicatesthe arrival of steam and then move down the line to a new cold section of main and repeat...

Thank you for the advice on the vent I will def be ordering one of those. 

To clarify your saying to start the boiler up after it’s been dormant long enough for those pipes to be free of any residual heat from the last cycle. Then to go along the main and see how far along the pipe gets hot before the low water cutoff? How can I tell the difference between steam and hot and condensate hot? Temperature? Also a bit of an update this morning the first of the problem radiators along the main actually got heat today. This was after we changed how set the thermostat. Instead of turning it off at night and allowing it to get down to about 58-60 degs we set it to 63 and I heard it kick on a few times during night and early morning. So that makes me a little hopeful that when my pipe insulation arrives this week and I can install that hopefully that will help with some of our problems.

The amount of times the low water cutoff is being triggered is a bit worrying to me, it doesn’t seem normal. How many times is normal for the low water cutoff to occur? Just this morning I watched it for about 15 minutes and the it hit the low water cutoff 3 times in just those 15 minutes. That seems wrong to me. 

mattmia2

Maybe it is surging. The installer should figure that out and fix it. Where is the skim port?

Fixing the unstable water level is the first step in fixing your problem.

dabrakeman

I will defer to the true experts here (@Jamie, @Steamhead etc...) since tjohnson2342 says that they did not have the issue with the old boiler and his lwco seems to be shutting down the boiler frequently with site glass water level truly dropping might there have occurred some kind of partial blockage in the condensate return with the new install?

tjohnson2342

mattmia2 said:

Maybe it is surging. The installer should figure that out and fix it. Where is the skim port? Fixing the unstable water level is the first step in fixing your problem.

I agree, the installer should figure and fix it. I would honestly need another post to highlight the problems we’ve had with this gas conversion and install, if our old boiler hadn’t broken down twice last winter and we didn’t feel such an urgency to get a new one, I def would have done a lot of things differently this year. 

To answer your question though, skim port is in the back.

mattmia2

You should try skimming it again, maybe a couple times, and see if that calms things down. Someone more versed than I can post the procedure or you can look in the manual. The basic idea is you want the surface of the water to run slowly out the skim port.

BobC

1-1/2" mains can only support about 65 of EDR so make sure your not trying to feed much more than that

The Gorton #2 is a pretty tall vent, if you don't have the height to support that try multiple Gorton or maid o mist #1's on an antler, a #2 is about 3-1/2 times the capacity of a #1 vent. The Maid O Mist #1 is half the price of the Gorton and I've found them to be reliable over the last 8-10 years.

I've attached the Peerless "The Color of One Pipe Steam" which is a great compact reference of single pipe steam. They also have a smlilar booklet for 2 pipe steam.

Bob

Hap_Hazzard

The U.S. Boiler manual doesn't mention skimming, but Peerless & Weil-McLain do, so I'm attaching them here. I'm also including an article from Oilheating Magazine, by the technical training manager from Weil.

The Peerless instructions recommend adding washing soda (aka sodium carbonate or soda ash). I've always done this, and I think it helps. They also say to fill and drain the boiler afterwards to rinse out all the washing soda, but the guy from Weil-McLain mentions using it as a water conditioner, so I don't think it hurts to leave a small amount. I will say that you shouldn't add washing soda to a boiler—especially an older one— unless you're going to flush it thoroughly, because it does tend to loosen any scale or rust, and you want to get that out before it settles to the bottom.

mattmia2

Leaving the washing soda in could make it prime depending on how much and your incoming water chemistry.

Hap_Hazzard

mattmia2 said:

Leaving the washing soda in could make it prime depending on how much and your incoming water chemistry.

Definitely. You should always check the pH of the water before adding any treatment you intend to leave in. Too low, causes corrosion. Too high, causes foaming. Foaming is bad because it pushes water out of the boiler and prevents LWCO probes from sensing the true water level.

Charlie from wmass

1. New #33 Vent Rite air vents on convectors. 2. Stop skimming. It's not oil. 3. Confirm pitch on Supply. They may be running around backwards on the supply loop.  

ethicalpaul

Insulation is fine but I don't see it solving any of the actual problems that you've listed in this thread.