Hot Topics: Steam Heat Banging Noise

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Original Post: Steam heat - Loud banging noise from the pipes

stuck_old_house - Member

Steam heat - Loud banging noise from the pipes

I have this old steam heating system in my house that I purchased a few months ago in Summer time.

Now in winter when the boiler was turned on, (and after fixing the leaks in the pipes), I'm finding myself in this mess where all the pipes are making loud banging noise when the boiler kicks in. It's a Crown boiler and I don't know how to tell if it is a two pipe or one pipe system, but my guess is that it is one pipe. I wake up in the middle of night every night due to these noises and soon my tenants are going to come to me and complain about it.

The little glass pipe by the boiler, that shows the water level, has always been full ever since the boiler was turned on and I was told that this is where you can check the water level. Is full glass pipe, too much for the system? is it the reason for the noise?

I could really use some help here.

Is there anyway I can fix this myself with some guidance from the experienced people here. I do not want to spend thousands of dollars to convert the system into another type or anything in that direction.

I'm a newbie for all this stuff, it's the first home I ever purchased and will not buy an old house again. I'm so frustrated with all the things I had to get fixed in here.

Appreciate any advice here.

Grady - Forum Topic Moderator

Glass Pipe

It sounds like your boiler is flooded. Most boilers have one or two line(s) on them showing the min. &/or max. water level. Make sure the valves on the sight glass are open & drain water until the gauge shows aprox. half full.

stuck_old_house - Thread Starter

Thanks for the response. I'll try taking some water out of the system.

I believe the valves for the glass pipe are open because when the boiler is off, the water seems pretty clean and transparent, and when the boiler is making steam, the water is black and dirty as hell. So I think water is flowing thru the glass pipe BUT the level of the water is always full which is what I'm going to try to bring down tomorrow.

However, I want to make sure I'm doing the right thing. I just have to open the main drain pipe and watch the level of the water go down in that glass pipe until it's 1/2 full?

If I drain too much, the boiler should be able to take what it needs from the feeder or am I wrong? I hope it won't damage the boiler.

Grady - Forum Topic Moderator


You are correct in you should drain from the bottom of the boiler & if you drain too much, the feeder should make up the difference. This is an excellent chance to test the low water cut-off as well.

Turn off power to the boiler.

Turn off water to the boiler.

Drain the boiler so there is just a little water showing in the sight glass.

Turn on the power. Boiler should NOT fire.

Turn on water. Water should feed & once water reaches high enough level, burner should fire, presuming there is a call for heat.

Did you find any markings on the boiler regarding water level?

I often use a Sharpie to mark the sight glass at min & max levels as an easy reference.

stuck_old_house - Thread Starter

Happy Thanksgiving to all!

OK, I finally got a chance to drain the entire boiler out.

The water was dirty and black for the most part. I don't know how bad it is for the system?

Anyway, when the boiler was turned on, the water feeder made a click noise, and I saw that the red button (for manual water feed) popped into the little box and water started pumping into the boiler.

BUT it stopped after the glass pipe showed the level as 1/4th fill. I know I can't turn the thermostat on like this, because that level of water isn't enough, right?

So, I don't know if it has fixed the noise, but I'm waiting for someone to repond and let me know if I should feed more water into it? If yes, then to about 2/3rd level in the glass pipe, right?

Please help. I know it's Thanksgiving and I need to get a life, but right now I need some help.

Furd - Member

If you have any water showing in the glass it is safe to fire the boiler. One-half glass is normal and 2/3 glass may be too much when the boiler is cold.

If you have 1/4 of a glass when cold it may very well "swell" to close to a half-glass when it starts to steam.

Grady - Forum Topic Moderator

Looks like you may be becoming a addict like many of us here. Holiday? What's that? Mechanicals know no holiday. That being the case, mechanics know no holiday.

It is not at all unusual for the water to be black, rusty, & generally cruddy.

That may be enough water. We need to test the low water cut off. Turn the thermostat up & the feed water off. Now open the blow down valve & allow water to drain. Within a couple of gallons, the burner should shut down & the button on the feeder should pop. If it does, that's good. Open the feed water valve, let it feed, & the burner should fire. You didn't find any lines on the boiler, usually near the sight glass which would indicate minimum & maximum fill levels?

stuck_old_house - Thread Starter

Thank you Furd and Grady. Thanks thanks and thanks

I tested the water feeder and it works.

Yes I finally found the line on the glass which is at 2/3rd level.

Now that said, Grady you were right, the boiler was flooded. It only filled itself to 1/4th level, but I pumped a little more to make it between 1/2 and 2/3rd level.

So, now, some of the pipes and radiators have stopped making that noise but some are still.

But a new thing came up, one of the radiators was never heating up and suddenly it started heating up today in the tenant's apartment. However, it is making continuous noise from the bleeder valve, as if the air is coming out very fast and it won't stop. (I tested it for 5-10 minutes and then shut the thermostat off to make the noise stop).

Is this something that every radiator does when it heats up for the first time?

I hope I don't have to call someone and pay just for this.

And again, thank you so much for all the help.

Grady - Forum Topic Moderator


Once the radiator gets good & hot all the way across the venting should stop. If it does not, you may have to remove & clean the air vent or replace it. For those radiators not heating, remove & clean or replace the air vents for starters. As to those still banging, I'll defer to Furd. He's far more familiar with steam than I.

stuck_old_house - Thread Starter

Grady, Thanks, I'll wait to see if Furd gets a chance to reply on this.

One quick question, the air valve was really hot to touch on this radiator that just woke up today. And the radiator was very hot down to the last fin where the valve is and the valve was still hissing. I think it may be time to change the valve? I'll give it a few more tries and then see what happens and post here. Luckily I know how to change the valves, but what is the difference between the cylindrical shaped and the round shaped valves? I have a mix of both types from the previous owner of the house.

Grady - Forum Topic Moderator

Air vents

Some are adjustable while others have a fixed orifice. Obviously, the adjustable can help if you have a radiator which heats either too fast or too slow. The adjustable ones will usually have numbers or letters around the perimeter & usually a screwdriver slot on top.

Furd - Member

Air vents are cheap enough that trying to clean them is usually a waste of time. The exception is if you have adjustable air vents.

As for the banging...check that the banging radiator is absolutely level or very slightly pitched so that the steam pipe end is slightly lower. All of the piping must have a gentle slope all the way back to the boiler.

Always have the radiator valve fully open or fully closed. Do not try to regulate the heat by throttling the valve.

Check the pressure in the boiler. Residential steam systems do not need more than 2 psi and usually work best with less than 1 psi.

stuck_old_house - Thread Starter

Thanks Furd. I replaced the air vent with a self-adjustable one and it seems to be fine now.

The noise in the overall system has been drastically reduced (there is still a little different kind of noise, but I'll deal with it later). I think reducing the water in the boiler did the trick. Thanks to all you guys for your suggestions.

however, I did find that there is water leaking from one of the pipes inside the wall. There is a noticeable water leak on the drywall. I believe there should be an elbow inside the wall from which point the pipe goes upstairs and that is where it leaking. How hard it is to replace an elbow on a cast-iron pipe? A local plumber is asking $500 to break the wall and replace the elbow (provided that it is only the elbow that is leaking) and then fix and paint the wall back. Is this a reasonable price for replacing the elbow?

Furd - Member

I seriously doubt that your piping is cast iron, fittings may very well be cast iron but the pipe is probably steel.

$500. to open the wall, replace an elbow and then patch and paint the wall sounds very reasonable, in fact downright inexpensive, to me. Does this guy offer any references?

stuck_old_house - Thread Starter

Well, this guy has done some work for me in the past so I know him.

He came over today and broke the part of basement ceiling (where the pipes are) and guess what we found.

There is atleast 5 different pipes that are leaking (including the steam heat). Obviously the estimate went up to $3,000, and I feel so unhappy about all the money I had to spend in fixing up all the hidden broken stuff already and now this thing came up.

So, I could really use some advice here. Is there something that I can patch the pipes with for now and avoid spending $3000? The leaks aren't that big and the water is kind of dripping drop by drop.

I'll try to post a picture later today.

Furd - Member

I'll wait for the pictures before giving a complete answer but it may be that a bucket is your best bet until spring.

stuck_old_house - Thread Starter

Here are two pics I took that came out OK. Others were out of focus and I couldn't find my ladder to get up there to get better pics. I'll try to get more tomorrow. But the first one shows a T- joint that is almost rusted out, and I had a paper towel to soak up a little water.

I tried to mark the spots with arrows.

leaking pipe t-joint

In this one, it is the steam pipe that is leaking. You can actually see the drop of water in the air.

leaking water pipe

NJT - Member

Very cool... the picture of the water droplet, not your situation of course.

Off topic, but I might suggest that perhaps you need an electrician also. Did the plumber mention those wires ? That ain't right... I wonder how many more of that type connection are hidden inside your walls...

Furd - Member

Yeah, I definitely want to see some more pictures. In that first picture it is a copper water line that is seriously corroded and leaking. That valve should have never been "buried" in the wall.

I also see a steel line that appears to be not too old as it has teflon tape at the threaded elbow. Is this one of the steam pipes to a radiator?

That type NM electrical wiring is an accident waiting to happen. All splices need to be made properly in an approved junction box and they must remain permanently accessible and not buried behind a wall. You need to fix this.

In the second picture that pipe doesn't look real old although looks can be deceiving. I may be completely wrong but I get the impression that pipe is of foreign manufacture. That leak on the bottom would most likely have come about due to acidic condensate (fairly common in steam systems) and compounded by the inferior steel of foreign pipe. Usually acidic corrosion shows up at the threaded joints first.

I don't like saying this but you may have a really big (and expensive) job here.

Grady - Forum Topic Moderator


What a mess. I too wonder what else lies buried behind the walls. Scares me. I'm afraid I have to agree with furd about this job growing & getting expensive, fast. Sorry, but I've gotta call 'em the way I see 'em.

stuck_old_house - Thread Starter

NJ Trooper, yeah I kinda like that picture too , yes, I did think about it and that guy also mentioned fixing the wires, and throwing them in a junction box. He also said he could put a metal access panel in the ceiling, instead of closing it out with sheet-rock like before (just in case if something happens in future).

Furd, I'll post more pictures tomorrow. You are right, the pipes don't seem to be that old to me either, I guess it's just inferior quality material.

Grady, I guess my username here says it all, I'm really stuck here, especially in this economy when it is so hard to sell the house at the price you want. I don't think I can break-even at this point in time. I don't know what else might be buried inside those walls, but a lot of stuff wasn't done right.

So a question from a newbie, isn't this a common thing in old houses, breaking stuff, high maintenance etc. or is it just me - the lucky one

Grady - Forum Topic Moderator

Old House

It really depends on the previous owner(s) & if they wanted to spend the time & money to do things right or just get something working as cheaply & rapidly as possible. Sheet rock & paint cover a multitude of sins. Things like this are most common in the "low rent" areas.

NJT - Member

Sure was common here!

When we demo'd the 2nd floor about ten years ago to go up to full height ceilings, after living with a 6.5' ceiling for 15 years or so, what I found was pretty horrific as far as wiring goes. I'm surprised the place didn't burn down.

I went into mine fully aware that every system would need replacing though... but there were still surprises. 23 years later, I'm ready to start again, right at the beginning!

A lot of what you are finding are the reasons that many pros scoff at homeowner DIY'ers ... they see that stuff a lot.

stuck_old_house - Thread Starter

Well, I was able to seal the steam pipe leak with epoxy from HD. It has been working beautifully so far. The other leaks aren't that bad but I'm going to try same thing on those.

Now, there is a different issue, there was one radiator in the basement (sitting at pretty much the same level as the boiler), which had both it's ends kind of buried inside the wall and only the fins are exposed.

The smart contractor that was working on a major leak in a pipe, found out that the radiator wasn't hooked up so he opened up one end and hooked up to a steam pipe nearby and charged me for doing that.

It seemed to work fine till the day I reduced the water in the overfilled boiler. And since that day it just won't work and basement is cold and chilly now. While trying to find the reason for its failure, I put my camera inside (because the space is too tight to get my head inside and look) and took some pictures and found out that the radiator was already connected at the other end and so it is connected at both ends now. I don't know how it was working before. It has no air valve and I don't know how to make it work. Any suggestions?

V8toilet - Member

Help with steam heat

O-man you need some help! Since you are the owner of a very old house (I am too and I feel your pain) you need to get some information and educate yourself so that you can feel confident about what to do when these issues arise and know when you are hiring a pro or a knuckle head (most are knuckle heads).

Steam systems when they are set up right and are working right are awesome (have one in my home and love it). They can be as a system very efficient, super quiet, and very reliable, and very comfortable. The problem is most of them were installed before we were born and most of the people who installed them and knew how to service them are dead now. They did however leave us with tons of information on how they work, why they don't work sometimes, and how to fix them so they do work. There is one author in particular who is passionate about steam heat and took the time to gather and read hundreds of these books and put that information into just a few books so people like you and I could finally get some answers to our questions.

Years ago I was like you where I purchased an old home with steam heat. I asked many of the same questions that you are asking and had no clue what I was looking at. Now after educating myself I know more than most heating contractors do. My fuel bills went from $580 a month to $165 a month with the work I did to my own system and the home because I had the knowledge to do so from the books I read written by Dan Holohan and the great people on the Wall. The steam system in my home had some of the same issues you have with no heat on some rooms to cooking others with hissing valves and high fuel bills. Now the system is very balanced, quiet, and efficient and so can yours be too. This information saved me $$$$ and many many headaches. I wouldn't spend any more money if I were you until I got these books. $3000 is a lot of money to spend on repairing just a few pipes.

First you need to go to and get Dan Holohans books on steam heat found here in the store section. You can also post questions on the Wall where many steam heating pro’s like steamhead hang out and help people like you. I would start buy getting at least “We got steam heat” written by Dan Holohan because this book makes understanding how steam heat works very easy to understand and it’s cheap.

To know if you have one pipe steam or two pipe is simple. If your radiators have two pipes going to them than you have two pipe steam heat and they should not have any air vents on the radiators themselves unless you have a rare and very old vapor system. If you have one pipe steam than you would only have one pipe going to each radiator and an air vent. With one pipe steam the steam goes into the radiator and the resulting condensate goes out the same pipe and the radiators and the pipes are pitched so that can happen and you don’t end up with water hammer as you have said you had.

Now the above posters were correct in that the water level in that sight glass should be half way up the glass. The water quality inside the boiler also affects how well the boiler makes steam and can also cause water hammer. The steam pipes in the basement should also be pitched and insulated and if they are not that too could cause high fuel bills and water hammer because uninsulated pipes loose heat five times faster than insulated ones with 1” fiberglass insulation. The uninsulated pipes cause the steam to condense back into water before it ever reaches your radiators causing too much water to be present in the pipes at one time. The boiler runs longer to compensate for the lost steam to the uninsulated pipes wasting valuable fuel and some radiators may not even get steam because the uninsulated pipes are condensing the steam before it gets there. You want the steam to give off it's heat inside the radiators not inside the pipes leading to the radiators.

The water hammering you hear is the steam pushing the water down the pipe and smacking it into the first elbow it encounters. When your boiler was overfull too much water was getting up into the pipes and the steam was flinging it around inside. The near boiler piping is designed (if done right) to separate the steam from the water so you get what pro’s call dry steam not wet steam. Dry steam contains less than 2% moisture or water. You also need to check your steam pressure, which is one of the most important things. It should not go above 2 psi. If it does the pressuretrol may be set wrong by some knuckle head. Steam systems work best with low pressure not high pressure. If anyone ever tells you that you need a good head of steam to get the steam up the pipes than steer clear of them because they don't know what they are doing and he or she is a knuckle head.

If you want you can e-mail me with more questions and I’d be happy to help.

stuck_old_house - Thread Starter

First of all many thanks for your detailed response.

Now, that I'm stuck with what I have, I will have to deal with it, no matter what.

My heat bill was $495 this month which drove me crazy. I have to keep my thermostat at 78, because the first level gets hot and the tenants complain that their apartment is cold.

I have started insulating all the exposed pipes I can, with the fiber-glass insulation (I couldn't find anything for the bigger pipes, any suggestions on how to insulate the near boiler 2.5" pipes?). None of the pipes inside all the rooms had any insulation whatsoever (and they are inside the rooms not inside the wall).

I wanted to know, if I close a couple radiators that I don't really need to be hot, is it going to save that steam and use on radiators upstairs?

Another major problem is the radiator in the basement which is at the same level as the boiler. Assuming that the smart contractor hadn't connected it at both ends, and it did have a valve, how will the condensate go back to the boiler from it? (Because the pipes that it is connected to , go up and down a couple of times).

Here is picture of the radiator, he just opened the wall on the left and there happened to be a capped steam pipe there which he thought should be connected to the radiator. Turns out it was already connected on the right.

V8toilet - Member

Your uneven heat is most likely caused by inadequate venting of the system. On your mains in the basement near the end about 15 or so inches back there should be a vertical 3/4” pipe sticking out of the top of the main with a main vent on it and depending on how large your main is there could be two or three of those vents. Those main vents vent the air out of the mains quickly so that the steam gets to all the risers in about the same time and then from there the radiator vents take over. If the main vents aren’t there than the only way for the air to get out of the pipes is through the vents on the radiators, which are only designed to vent the air in the radiators and the risers leading up to them.

In order to steam to get to the radiators it must push the air present in the pipes out first. If the mains are not vented than the steam takes longer to push the air out of the pipes because of the lack of venting and the boiler runs longer because the steam takes longer the reach the radiators to satisfy the thermostat. Without proper main vents and radiator venting you end up with uneven heat in the building and the steam takes longer to reach the radiators farthest away from the boiler. The radiators that are closer to the boiler with the shortest runs and the least amount of air to expel also get hotter quicker and the radiators farther away sometimes never get steam in time before the thermostat is satisfied because the steam takes too long to push the air out of the way through those vents. The way to balance a steam system is through the proper venting and everything must be vented separately like the mains, the risers, and the radiators. It’s all in the venting!

You may not find any main vents and a lot of times with the older coal fired systems you don’t. This is because when boilers were coal fired they didn’t need to vent the mains and the rest of the system fast because coal fired boilers ran for hours and could not be shut off like oil or gas fired boilers can. Think about it! How do you turn off a coal fire? It didn’t matter if it took a long time for the steam to reach the farthest radiators after the coal fire was started because eventually it did and when it did it just kept coming for hours and if it got too hot in the room the people would just open the windows to regulate the heat. This is how it worked in those days. When oil became big many of the coal fired boilers and “systems” (means the system remained the same but they replaced the boiler with an oil fired one) were retrofitted with oil fired burners.

These oil fired boilers where on and as quickly as they came they went off as the thermostat was satisfied. Those system weren’t designed to work with a on off flame. Now all of a sudden you have these boilers that steam very quickly on systems designed for slow coal fired boilers and many people ended up with uneven heat like you have. As the people complained in those days they figured out that they now had to get the steam as quickly to the radiators as possible so they added large vents to the mains and sometimes vented the risers to the second and third floors separately from the radiators so that steam would arrive at all the radiators at about the same time and this put the system back in balance. They also vented the radiators according to there size (EDR) with different venting capacity vents. When a steam system is vented properly the steam moves through the pipes as quickly as 35 mph. I gave you the link to the place where you could get a venting capacity chart (only $10) to figure out what size vent you need for your radiators and mains

Now as far as that basement radiator what probably happened is originally that was a one pipe steam radiator like the rest of your radiators in the house and if it was than there should be an air vent on that radiator somewhere. Steam always goes from high pressure to low pressure (we’re talking just ounces of pressure not pounds) and if you don’t have a vent on it and two steam supply pipes than the steam can’t get in the radiator because the steam pressure is the same on both sides of the radiator because you have two steam pipes hooked up to it. If it was a two pipe system by design than there should be a thermostatic trap on one end with and one pipe should be much larger than the other. I can’t see the pipes in the picture but it does look like the radiator is pitched which means it was most likely originally a one pipe steam system radiator. As far as the supply pipe that isn’t pitched I don’t know and you’d have to post s picture. Look to see if you can find that vent on the end of the radiator about one third up on the end. You may find a pipe plug where there was once a vent. If so remove it and install and vent and see what happens or if there is one there it could be clogged so replace it with a new one.

You can shut the valve on those radiators you don’t need but those valves have to be either all the way on or all the way off. You cannot regulate the steam with those valves because the steam and condensate share the same space and if you only partially open and valve it just may water hammer. This may however make the steam get to those radiators that don’t heat because the boiler shuts off before the steam gets to them because you don’t have enough venting in the right places.

There is a band-aid fix however to try and balance the system if you don’t have main vents or provisions for them. You can go to Home Depot or Lowes and get Maid-O-mist steam valves in different venting capacities ranging from the smallest to the largest as 4,5,6,C,and D valves. You can either give me the EDR of your radiators and I can tell you what you need or you can experiment by putting the largest valves on the radiators that are large and don’t heat and the smallest valves on the radiators that are small and get too hot. You can get 2-1/2" 1" thick fiberglass insulation.

stuck_old_house - Thread Starter

What I found... I haven't seen on any other radiator in my house. As a recap, the right side this rad was always connected. The left side was connected by mistake by a contractor, so now it's connected at both ends with no air vent. On the pipe that was already connected to the right side of the rad, there is a valve (the one that is usually on the water lines like a handle), not the regular radiator valve. Also, the pipe actually comes down into the radiator unlike others where the pipe is connected so that condensate can flow back to the boiler on its own with the gravity. Is it possible that condensate can rise up into the pipe and then flow down to the boiler? I mean the boiler is sitting at the same level as (or maybe a little lower than) this radiator in basement, but the pipe goes back up and then comes down.

It doesn't (or didn't ever) have an air valve. It does look like there are some bolts on either end.

So my question is, is it worth even trying to get this thing to work? Can this thing technically work with steam heat? How will the condensate flow back to the boiler?

One guy even connected it to the other end without even checking that it was already connected, and created more work and I'll end up spending more to fix what he messed up.

Now that I know a little more about steam heat, all plumbers/contractors I have shown this to, seem to have no idea/knowledge/experience about how steam heat works. They pretend to know everything but sound like they don't know what they are talking about.

I wish I knew about this system before I purchased this house.

Thanks for any suggestions you may have. I really need some heat in the basement because it's completely finished.

V8toilet - Member

That radiator

From those pictures it looks to me as if that radiator is piped for forced hot water and not steam. Steam boilers can be set up to be both forced hot water and steam; if that is the case with yours than you should have an aquastat somewhere on the boiler along with a circulator pump. Follow the pipes, where do they go, and do you have these items? There should also be a bleeder valve at the highest point in that piping if it's set up for forced hot water to bleed the air out of the water.

If the plumber used copper pipe for steam and 3/4" or 1"pipe too than it just won't work that way. Steam pipes need to be larger and you should never use copper for steam pipes because copper can't take the expansion and contraction of steam heat and eventually it will fail. Condensate doesn’t flow up hill!

Now as I said before you can get that steam system working like you never thought it could but you need to educate yourself because as you said, and you are finding out, most contractors just don't know anything about steam systems. All of the guys who once did are dead now. You still can find good steam heating contractors who actually know about steam heat and many of them hang out on the wall at I HIGHLY RECOMMEND YOU GET THOSE BOOKS I TOLD YOU TO GET. At least get the $25 "We got steam heat" book I told you about.This book would get you on the right track and make all this stuff easy for you to understand. It’s basically steam heat in laymen’s terms. After reading the book you won't feel like doing this anymore but instead you'll be like this

V8toilet - Member

If you lived near Worcester MA I would come over there and show you what to do!

stuck_old_house - Thread Starter

Thanks to all for the replies and help here.

Now that things have settled down a little, I wanted to update this.

V8toilet - I thought I started to understand the concept a little, but over the last weekend, after I drained the boiler just to clean the water, the radiator in the basement started to heat up just like before. And it has no air valve still . But as long it is working, I'm not going to bother. My finished ground level looks beautiful again. I will look into getting that book you recommended. And no, I'm not near MA, I'm in NJ but I appreciate all your help.

I do have some noise problems (hammer in one radiator) and loud hissing noise from all of the air valves (yes I did clean 'em, replaced them etc.), but overall it's better than what it was before.

Grady NJ Trooper and Furd, I got that leaking pipe and the water pipe joints replaced and those wires in a junction box. No more leaks or safety hazard now.

Thank you all for your help. Now I have to deal with the hissing noise (I read somewhere that there is no solution to that, but I will keep looking)

finisher - Member


How exactly did u go about draining and cleaning the water in your system. I tp have been dealing with banging pipes since purchasing our (house) diamond in the ruff. I appreciate the help.

DavidB512 - Member

Knocking Steam Radiators

I'm having the same problem as stuck_old_house. My radiators are knocking, and the water level in my furnace is too high. I drain some water out, the level in the glass tube goes down, but it immediately returns to the top when I shut off the drain valve. Help!

Grady - Forum Topic Moderator

Too much water

Somewhere near the boiler's water feeder should be a shut off valve. Turn it off then drain water until the level stays where it should. Once enough water is drained, re-open the valve. The water level should no go back to the top of the glass. If it does, your water feeder is adding water when it should not.

stuck_old_house - Thread Starter

DavidB512, What kind of steam heat system do you have? One pipe, two pipe?

Do you have an automatic water feeder? Do you see a device that automatically triggers when water level goes too low?

mjwdive - Member

boiler, sight-glass vertical tube, losing water?

I have the opposite problem, rather then being too full, my water levels fall. ussually about evey 2-3 weeks, the boiler stops kicking on. When i go to the basement I find the water level in the glass tube have fallen too low. I manualy turn on the facet on the right of the boiler and fill it half-way. The boiler kicks on and runs fine for another 2-3 weeks. Not sure if it's the auto feeder? or if i have one. there is a value at the top and the bottom of the glass pipe. should they be open or closed? Any advise is welcome Thanks!

Grady - Forum Topic Moderator

Low Water

The one good thing here is you know your low water safety cutoff works. It sounds like there is no automatic water feeder. Some pictures of the boiler & near boiler piping would help. Wide shots & closer ones from various angles. You can post them on or similar site & provide a link here.

gold3nman - Member

New Boiler now banging

My boiled broke the other day in cold weather so in a pinch I got a new steam boiler rather then change it out with something better. I have been in my house for 5 years now. My old boiler was wonderful. Nice and quiet. Now with the new one installed. I get lots and lots of banging and the radiators "whistle". Lots of rushing air out of the vents. I do not think that the person who installed the boiler knew how to adjust it. There is a little gray box on the side of the system with some numbers on it and a "slider" that runs up and down. My old system had the slider close to the bottom. The knew one has it almost to the top. Watching the pressure in the system it gets up to about 4psi after it has been one a while and all radiators are hot. Any ideas? If you need pix I can send them.


Grady - Forum Topic Moderator

Four pounds is usually way too high for a residential boiler. Often they run at 1-1.5#. Rarely over 2#. I suggest you call the installer back. Let's hope it was just an oversight.