Unbalanced Steam System?????????

FXProglJr

I have a problem and would appreciate any help or suggestions you can provide.  Grandpa's house is a 1928  brick 2 family/story house that originally had separate coal furnaces for each apartment.  The heat was single pipe steam (but the ends of the mains in the basement were ended in a tee with a vent on the top of the tee and a condensate return on the bottom of the tee) .  In the 1950's, grandpa had the coal furnaces removed and one oil furnace installed.  The installer left the separate mains but just joined them together over the new furnace.  The thermostat was in grandpa's apartment on the first floor and there were never any complaints from tenants about heat. (But the building did seem to use a lot of oil)  I've inherited the house and now find that when the thermostat is set at 70, it is 70 on the first floor, but the second floor in over 80 (no wonder that there never were complaints),  I changed the vents on all the 2nd floor radiators to the smallest hole I could buy (and even plugged them up with toothpicks so that the radiator on the 2nd floor don't get hot all the way across) and all the radiator vents on the first floor to ones with the biggest hole I could find, but when it's 70 on the first floor, it's still 76 on the second floor.  I have the pressuretrol set to cut out at 3lbs and back in at 1-1/2 lbs.  I've opened the main and the return for the first floor just to look inside but found them to be clean and clear.  There are 5 radiators on the first floor (2 seem to get very hot and 3 not so hot) and 6 radiators on the second floor (all get hot).  I think I've eliminated problems everywhere except the pipe between the main and each of the radiators that don't get so hot and the  radiators themselves (they are cast iron and pretty heavy).  I'd sure appreciate hearing any suggestions you may have as to how I should proceed.

JStar

Balance

It's possible that the main vents are not working properly, and the steam is favoring the second floor radiators. How long does it take to get steam from the boiler to the end of the mains?



The pressure is also way too high. It should be set as low as possible (about 1.5 psi). Most systems will run on just a few ounces of pressure. The radiator vents will also be damaged by any pressure over 2psi and may not function properly at your current settings.

gerry gill

how about

thermostatic radiator vents on the second floor.

Steamhead

Where are you located?

there may be someone in your area who can help. 

Hap_Hazzard

What are the EDR totals?

Adjusting venting can affect which radiators get steam first, but it can't change the EDR. If you can identify and measure your radiators, we can help you calculate the EDR. If there's a major disparity, there are things you can do to change the effective EDR of radiators, like radiator covers that either enhance or impede the convection of air around them.

Paul48

Mains

Does each main have its own riser from the boiler header? Is that 70* first floor temperature an accurate representation of the whole floor, or just the room where the thermostat is placed?

nicholas bonham-carter

2nd floor too hot

Let's assume that the radiators were all piped properly on each of the original two systems, and therefore that any unbalance in distribution comes from the inadequate venting or the piping which now connects both systems to the one newer boiler. Can you post some pictures of the piping above the boiler, and the vents?

The first step should be adding a Gorton 2 to each dry return, and as others have suggested, reduce the pressure, (my 55 rad system rarely exceeds 6 ounces).

Are there any other symptoms such as water-hammer in the house? What sort of thermostat is controlling things, and is it set for steam? Have you been setting back the temperature during certain periods of the day?

You may have inefficient wet steam reaching the ground floor, and more perfect dry steam getting upstairs.

At the end of this you may see a fuel consumption drop by a third.--NBC

FXProglJr

BALANCE

WOW!!  Thanks for your

input and sorry, I’m new to this site and was expecting to receive an email

whenever anyone posted a response.  I was

just checking to make sure that my original post was still here when I saw that

many of you have already provided input.  I’ll try to answer your questions:



I've checked the main vents and they're working ok.  I've already changed all the vents on the first floor radiators.  (I find it strange that a radiator at the end of the main seems to be getting better steam than radiators much closer to the furnace.) 



It's not heating season yet, so I'm going to pull a first floor radiator and check for clogs and then check the short pipe between the radiator and the main - I'll let you know how that turns out.



I'll try changing the pressure, but I have 2 other houses on this street with esentially the same heating system.  They're all set for 3lb cut-out and 1-1/2 lb cut-in and working fine.  (When I obtasined one of the houses and checked, it was running at 10lbs cut-out and 8 lbs cut-in....I changed it, but iot was working with no complaints.)

FXProglJr

how about

Thanks for your thoughts....it may come to that, but I'd like to exhaust all other possibilities first

FXProglJr

where are you located

I'm in Middle Village, Queens, NYC

FXProglJr

Mains

Thanks for your input and sorry for the delay in getting back.



I've attached a sketch showing the boiler piping to the mains.



The 70* on the first floor is fairly even in all the rooms (except the bedroom - furthest from the furnace - where Grandpa put in a smaller radiator because he liked a cool bedroom.

FXProglJr

2nd Floor Too Hot

Thanks for your ideas



I've attached a piping layout for everything in the basement.



The mains end in a TEE fitting with a vent on top and the return on the bottom.  So I don't think more vents are needed. 



 As you can see from the sketch, the returns on the right are joined together, drop to the floor and then rise again to get connected to the furnace line.  However, the returns on the left are separate and different.  One is a wet return and the other is not - is this a potential problem? (but there are problem radiators on the first floor on both the left and right side)



I'll get to lowering the pressure later after I rule out clogs in the radiators or short pipe between the radiator and main.



There was some water hammer in the only radiator on the first floor that really gets hot, but I solved that by raising the radiator a bit to improve the pitch in the pipe.



The thermostat is a Honeywell TX500 electronic thermostat that I've set the differential for 2 degrees.....there is no setting for steam.



The temperature is set for 70* during the day and 65* at night.



Sorry, I'm not familiar with wet steam or what causes it, but will have to get into that if nothing else works.



Anyway, I'll let you know what I find in the first floor radiator(s) and the pipes that connect them to the main.  Somehow I suspect that's where my problem lies.

STEAM DOCTOR

Clogged rad

I wouldn't bother pulling the radiator. Radiators don't clog. The first thing to check is the main venting. Size is critical. It is nearly impossible to balance a steam system without proper main venting.. Wet steam could also contribute to uneven steam distribution.

I am based around the corner from you. Feel free to contact me.

FXProglJr

EDR totals

thanks for your thoughts, but I think my problem is much more basic than that.  I mean, some radiators on the first floor are just not getting hot enough.  I suspect a clog in either the radiator or the short pipe that connects the radiator to the main in the basement,



Here's what I found while researching this problem as a possible cause:





There's sludge in the horizontal runout to the riser.



This often happens after a one-pipe steam system floods. Water works its way up into the radiators, and the sludge washes down into the horizontal runout to the

riser. A puddle of condensate gathers around the sludge, causing the steam to condense.

The radiators won't heat properly because the steam can't make it past the

sludge and the trapped condensate. If you remove a radiator and shine a light

down the riser, you'll see a reflection. That's the trapped water.



Break the riser at its base and flush it from the top under pressure from a

garden hose.



I'll let you know how I make out

FXProglJr

Cloged Radiator

But here's something I found while researching this problem that makes the most sense to me:









There's sludge in the

horizontal runout to the riser.





This

often happens after a one-pipe steam system floods. Water works its way up into

the radiators, and the sludge washes down into the horizontal runout to the

riser. A puddle of condensate gathers around the sludge, causing the steam to

condense. The radiators won't heat properly because the steam can't make it

past the sludge and the trapped condensate. If you remove a radiator and shine

a light down the riser, you'll see a reflection. That's the trapped water.



Break the riser at its base and flush it from the top under pressure from a

garden hose.



I'll let you know how I make out

nicholas bonham-carter

Clogged pipes

Steam pipes rarely get clogged up, as they are being constantly washed with distilled water.

What does happen is the sagging of pipes, creating little waterlogged pockets preventing air from moving out of the way of the steam. Air is the enemy, it must be chased away like the raccoon from the garbage can.

When the system pressure rises above 2 psi, the vents have trouble working, and may let the air out more slowly, requiring extra fuel from your $upplier to finally get steam into most of the radiators, but not all. The fact that you have main vents is good, as the new replacements will be much easier to install. The capacity of the vents is the most important aspect of good balance. The size of the main vents, should allow for almost zero resistance (back pressure=2 ounces).

If you fire the boiler and feel the movement of warmth as the steam starts to rise, you may find a trouble area, which can be investigated, but changing the vents first makes this easier.--NBC

FXProglJr

Clogged Pipes

Thanks again for your interest/help. 

When I first noticed this problem I tried feeling the mains as the furnace began to make steam.  But they all seemed to get really hot, really fast.



Then I ran across this article on a heating help site as a possible cause:





There's sludge in the horizontal runout to the riser.





This often happens after a one-pipe steam system floods. Water works its way up into the radiators, and the sludge washes down into the horizontal runout to the

riser. A puddle of condensate gathers around the sludge, causing the steam to condense.  The radiators won't heat properly because the steam can't make it past the sludge and the trapped condensate. If you remove a radiator and shine a light

down the riser, you'll see a reflection. That's the trapped water.



Break the riser at its base and flush it from the top under pressure from a

garden hose.



So far everything has checked out, so a clogged radiator, or a clog in the short pipe between the main and the first floor radiators seems to make sense.  Removing the radiator  and checking it as well as the pipe down to the mail is my next move.



I'll let you know how I make out.

Fred

What about the boiler and near Boiler piping?

First of all, the pressure is set way too high. The Pressuretrol should be set to cut-in at around half a pound and cut-out at about 1.5 lbs max. It doesn't take much pressure to move steam through the system. As a matter of fact, if you've read Dan's books, you'll learn that the lower the pressure, the faster the steam will move through the system. Sounds counter intuitive but it's true. A couple questions I have: Have you measured the EDR of your radiators, in total and verified that the boiler is sufficient to handle that capacity? Someone combined two boilers into a single system which is cause to wonder if they properly sized the new boiler. The second question I have is what diameter is the header over the boiler that the two mains are tied to? If it is the same size as the mains and/or the riser from the boiler, it may not be sufficient to supply both mains at the same time. It should be at least one size larger than the riser from the boiler. Looking at your diagram, it looks like you only have one riser from the boiler to the header. After measuring the EDR of your radiators, if the boiler is properly sized, it may be necessary to add a second riser (if the boiler has an additional tapping) You can only push so much of anything through a given space at any given time. I'd start by verifying the boiler is properly sized right and that the header is at least 1 or 2 sizes larger than the riser and the mains. I think you are probably going to be wasting your time looking for sludge in a radiator or a radiator run but maybe you need to satisfy your own curiosity, like many of us do. 

FXProglJr

Boiler & Piping

WOW!!  you are way ahead of me, but I'll try to answer your questions.



First, even though all of your questions make sense to ask, would a problem with any of them cause too much heat upstairs and not enough downstairs?



I'll get to changing the pressure as soon as heating season starts.



I just learned about radiator EDR and, if I add all of the radiators in the house, I get a need for a little over 76,000 btu/hr.  The boiler hast a net IBR rating of  113,000 btu/hr for steam (which makes sense because I seem to remember back when Grandpa had it installed, the installer commented that it was bigger then necessary)



The header over the boiler is 4".

The riser from the boiler to the header is 2"

The mains are 1-1/2" each

The returns are all 1"

The pipe that goes from the header back to the bottom of the boiler is 1-1/4"

All of the taps going from the mains to each individual radiator are 1"



I don't know about an extra tapped hole in the boiler yet, but I'll check (and I hope it doesn't come to needing it)



And thanks for understanding that some people need to satisfy themselves that something is not a problem before moving on to another possibility.  I have pulled one of the radiators on the first floor that didn't seem to be getting hot enough (in fact, it's the one right overt the boiler) and took a look inside.  There was some rust in there but not enough to be concerned about.  Then I removed the valve and took a look down the feed pipe.  It didn't look bad either, but then again, I could only see down about 8" to the first elbow.  Guess I'll need to get a little camera down there to satisfy myself that it's clear

BobC

Sq ft not BTU

Forget about the BTU rating on a steam boiler. The boiler has to be rated to deliver the sq ft of steam that is needed for the total EDR of the radiators The sq ft of steam rating on a boiler includes a 33% pickup factor so don't add that in, in fact if the house is well insulated and the steam pipes as well you can cheat on the required sq ft rating.



I'll second the recommendation about lowering the steam pressure, mine is set to 12 oz and that is more than enough.



Bob

Fred

Hot upstairs

Steam is going to take the path of least resistance, first. If it can (for whatever reason move through that main and the second floor runs easier, then that is where it is going to go first and most. Check the vent on the first floor main. I know you said there is a vent on there but is it actually working? They will fail, especially if the pressure has been running high. Take it off and see if you can blow through it. What type vent is it? If it's an old one (maybe even from when the coal boiler was installed) it probably should be replaced with a Gorton #2 or a couple Hoffman #75. If you are sure the vent is working, make sure all the radiator vents are also working and equally important is to make sure all the radiators are pitched back towards the steam pipe. The problem has to be either at the main vent, the radiator vents or the radiator pitch. Also make sure the steam valves at the radiators in question are all the way open. Even though they are turned fully open, old valves sometimes break loose internally and don't function. On a single pipe system the valves must be fully open for heat or fully closed, no in-between. Sounds like the boiler may be a bit over sized (but you really need to calculate the EDR) which may cause some short cycling of the burner but there should be plenty steam. 1.5 inch mains seem a bit under sized but if it gets the steam to the second floor, it should be able to get it to the first floor as well. Is there an open staircase to the second floor? If so, that will act like a chimney and heat will rise up that staircase. I have a 3 to 4 degree variance between my first and second floor as a result of an open staircase. Also, are both mains insulated? Once you calculate your EDR, look at the rating plate on the boiler (same plate that has BTU's). It will give you the square footage rating that should be at least what your radiator EDR totals, hopefully at least as much and not too much over..  . ,

FXProglJr

Clogged radiator

Ok...I've pulled one of the two radiators on the first floor that doesn't seem to get hot enough (it's located directly above the boiler).  The vent is new and working.  The shut-off valve is open and clear. And, when I look down the pipe, it seems to be clear too (even though I can only see down to the first elbow -about 8" - - but I did get a snake in there about 3 feet and it came out clean).  So I guess I can remove a clogged radiator/branch pipe from my list.  What can you tell me about "wet steam" and where are you located?



thanks 

FXProglJr

EDR totals

well....I've calculated EDR's.  It seems I have 142 on the first floor (4 rooms + bath) and 177 on the second floor (5 rooms + bath) and a furnace that's good for 471.  So - it seems the furnace is big enough.  I think this is barking up the wrong tree and here's why:.



I have closed the holes in the vents of the second floor radiators so they don't get hot all the way across (see attached) but the second floor apartment still gets too much heat.



...I mean, I need to find out why some radiators on the first floor don't get hot all the way across (the vents are good), while another one (further from the boiler) does get very hot.  I'm sure I all the radiators got hot all the way across, my problem would be solved.

FXProglJr

Hot Upstairs

Ok...I've pulled one of the two radiators on the first floor that

doesn't seem to get hot enough (it's located directly above the

boiler).  The vent is new and working.  The shut-off valve is open and

clear. And, when I look down the pipe, it seems to be clear too (even

though I can only see down to the first elbow -about 8" - - but I did

get a snake in there about 3 feet and it came out clean).  So I guess I

can remove a clogged radiator/branch pipe from my list.



Now, to answer your questions:



I agree that steam will take the path of least resistance, but can't seem to figure why so much goes to all the 2nd floor radiators, but only 3 of the 5 first floor radiators.



Grandpa's furnace is in the middle of the basement and each floor has a 1-1/2" main to the left and another to the right.  And each end of each main has a Gorton No1 vent that is working - so I don't think venting is a problem.



All of the radiator vents are new with slow venting (small hole) on the second floor radiators and fast venting (big hole) on the first floor radiators.



All of the radiators are pitched correctly, but maybe I should try tilting them a bit more.  I'll do that before heating season starts.



I've calculated EDR's.  It seems I have 142 on the first floor

(4 rooms + bath) and 177 on the second floor (5 rooms + bath) and a

furnace that's good for 471.  So - it seems the furnace is big enough.   It does not short cycle.



There is no open hallway between the floors.  There are separate apartments and the tenants close their doors.



I'm still trying to figure what would/could keep steam from getting to a radiator.



Thanks for your thoughts

BobC

How?

How long is each main and are they sloped so water can easily find it's way back to the boiler. You may need more than a Gorton #1 on the mains and if there is any dip along a main or radiator runout there might be water pooling in the pipe. Pooling water will collapse steam and can cause water hammer.



Post some pictures showing how the mains were joined AND how the returns were joined as well. If it wasn't done right it can cause problems like you are seeing.



Bob

nicholas bonham-carter

Simultaneous arrival of steam

If you have an IR camera, then you an do a bit of running as steam is rising and capture the heat situation for some representative radiators on each floor. Choose the fastest and slowest. They should all get steam at the same time, when you are done.--NBC

BobC

If your diagram is correct

and there are returns that tie together above the water line that could be your problem. All returns should tie together well below the boiler water line.



Bob

FXProglJr

the diagram is correct

thanks for your input and yes, the diagram is correct.  The furnace is in the center of the basement. and it feeds a 1st floor main section to the right and a 1st floor main section to the left.  There is a similar setup for the 2nd floor.  The returns to the right are tied together at the end of the mains, drop to the floor and return as shown.  The returns on the left side are separate with one connected below the water line (but not by much) and the one for the first floor piped straight down.



While I would consider re piping the returns on the left so that they drop to the floor (like the ones on the right), I must say that on the last section I described above (the one to the left of the furnace for the first floor) there is a radiator directly above the furnace that doesn't get very hot, while a radiator connected at the end of the main does get very hot.



Do you still think this could be a problem?

FXProglJr

HOW?

Each main is 25 ft to the left and 25 ft to the right of the boiler and each end of each main has a GORTON No 1 (total of 4) .  I'll need to check to make sure that there are no dips in the mains, but there is no water hammer - can there be water pooled in as dip that does not cause hammer?



Again, I don't believe venting is a problem because all of the 2nd floor radiators get very hot, but only some of the 1st floor radiators get very hot.



I've attached some photos I have handy...the one for the return is pretty good.....the one showing the over boiler piping isn't - if you need something better, let meknow

FXProglJr

IR Camera

I borrowed that camera (expensive item) and no longer have it.  It was pretty neat and I had it long enough to see that all 6 of the second floor radiators get very hot, but only 2 of the 5 first floor radiators got very hot.......and one problem radiator was directly over the boiler......so I'm still looking for something slowing the steam to only some of the 1st floor radiators

BobC

Steam is lazy

it will go wherever it finds a path of least resistance. Having returns tying together above the water line might make it easier for it to head upstairs instead of going to the radiators on the first floor. No guarantees but it might well be a cause. If the systems worked fine when they were separate, something happened when they were tied together.



If steam comes across water lying in a dip it can bang but sometimes it doesn't, steam is not only lazy, it's fickle.



Bob

Paul48

Piping No-No

There should be 4 risers coming off the header.Teeing into the center of mains is not the way to do it.

nicholas bonham-carter

Wet steam

Probably, the 2 boiler piping setup worked imperfectly, but the symptoms were masked by the separate thermostats. If both had been connected to one thermostat, the symptoms would have been the same.

Do you see much movement in the waterline while the boiler is firing? The boiler may never have been cleaned properly when it was first installed (see skimming). Dirty water could produce a lot of wet steam for the ground floor, which makes those radiators slower to heat up. By the time the thermostat is satisfied, the upstairs is roasting. So first step would be to clean the boiler (not with chemicals!).

What sort of radiator vents are you using? Proper venting requires large main vents, and slower radiator vents (Hoffman 40). The pressure should be set as low as possible, and verified with a low pressure (0-3 psi) gauge.

Have you looked up the specs for the boiler (Peerless ?), to see whether that one 2 in.riser is adequate? Certainly the joining of returns above the waterline is incorrect.

Wrap some insulation around the pipes to cut down further on the wet steam problem.--NBC

ChrisJ

Late

I'm joining the discussion late but a few things stuck out to me.



First, the boiler isn't piped correctly and the way the single riser goes up into the header looks like it would produce wet steam in my opinion. I'm surprised it doesn't hammer on startup.



The second thing is covering radiator vent holes won't necessarily work. The reason being you need to break the vacuum every time the system cools down otherwise steam will keep finding it's way into radiators. You would think this wouldn't happen as the pipes should be big enough for things to equalize but they don't seem to for some reason.



If it was my system the first thing I would do is have the boiler repiped correctly with a drop header and have all the separate mains tied into the header directly. At the same time have the returns corrected as well so they are connected below the water line.



Next I would install Danfoss TRVs on every radiator on the second and third floor, or at least most of them. Vent speeds are important with these as well, If you vent too slow you won't get heat when you can and if you vent too fast you won't give the TRVs time to react and will still continue to overheat the room.

Fred

Diagram

Are the radiators that don't heat well all at one end of that horizontal main? If so, I suspect the steam is going in the direction of the section where the 2 radiators are that get hot and then any remaining steam is trying to backup into the other half of the main where those three radiators are. If my theory is right, you would be well served to separate that main into two that  both feed directly off of the header and while you're at it do the same for the second floor. I suspect fixing the first floor will create a similar problem on the second floor if that main is left as is.

RobG

Pressure

As most folks have already pointed out, there is no point in trying to troubleshoot the system until the pressure is under control. Please do that before posting more. With the pressure that high it will wreak havoc on your vents and there is no point in going further



Rob

FXProglJr

Pressure

Thanks for your thoughts.  But, as I've said earlier, I have 3 houses on this street with essentially the same heating system (some differences in piping) that are all set up with the same pressure.  The other 2 are working fine.



So - even though pressure may need to be lowered (I will take care of that) - there must be something else causing the problem and that's why I'm seeking advice here.

Paul48

Seen it

There's been pictures of systems posted here, that shouldn't work at all, and yet the homeowners claim they run flawlessly.  When there is a problem, there's no alternative but to go by the book.Proper piping, proper pressure, and proper venting are all required. Your piping and pressure are incorrect.Your venting can't be checked properly until you fix the other two things.

RobG

Three Houses

As you said "I have three houses all running at the same pressure" all that means is that you have three houses that are running at the wrong pressure. Lowering the pressure is the starting point. It's Free! It's easy! And it will save you money! You keep going back to the blocked returns from some blurb you found on the web, forget about that for now. Unless your boiler is flooding or cutting out on low water your safe on that issue. This is a process, you have to start at the beginning. If you don't believe that you are getting great advice here from people that know of what they speak you may want to look elsewhere for advice. 



Rob

ChrisJ

3lbs?

Any bit of extra pressure you produce above what is required to heat the house wastes fuel.



I heat my house most of the time at around an ounce or less.

You're running 48 times the pressure I am.



Besides excessive fuel consumption it's also harder on vents and the people living in the home due to the unnecessary noise.

RobG

As a comparison

As a comparison to your steam pressure. The Empire State Building runs at under two pounds of pressure.