Radiator knocking

[mindstalk.livejournal.com]

I grew in an old home with hot water radiators, and sometimes there'd be loud annoying knocking. But we were always able to bleed out the air bubbles. After leaving home, I've lived in hot-air heated homes. Or with steam-radiators in college. Until now, where this old apartment building, with radiators I'll assume are hot water, has the loudest and most persistent knocking, and the landlord says basically "welp, it's an old building, nothing we can do". Is this normal for the area, and I should make sure to only live in differently heated places if it bothers me? Is there nothing they could do, or are they just too cheap to do it?

*googles* Apparently steam systems can knock, or "pound", too, due to water trapped in the system, lovely. I don't know which is more likely, given that at bad times I can feel the floor vibrate, and the floor up by one of the pipes seems damaged. (There's naked pipes running from floor to ceiling, so simply turning off the radiators doesn't help noise.)

Comments

[steeks99.livejournal.com]

Not that this is helpful, but the lady friend had a similar problem in her former apartment. Landlord didn't seem to care, or at least seriously doubted how LOUD it would get in the very early am. Not a pleasant way to live. And we couldn't find a good solution either.

[misterthorn.livejournal.com]

It can be fixed. The triple-decker I used to live in had the worst pipe noise imaginable. It sounded like multiple people with multiple sledgehammers pounding as hard as they could on the pipes right inside your skull. Landlord paid someone to drain the heating system in the house, and then it was silent for a couple years.

[unferth.livejournal.com]

I'm no expert, but it seems to me that you should be able to distinguish steam radiators from hot water radiators by checking for air valves. A steam radiator will have an air release valve to allow steam from the boiler into the radiators, and those will audibly release the air inside the radiator each time the boiler starts up. As I understand hot water radiators, they shouldn't vent air under normal conditions.

Also, if there's only one pipe into each radiator that's definitely steam. The hot steam and cooler condensed water share the pipe.

It's worth knowing which of the two you have, since that affects how easy it is to do anything about it.

[annalauwa.livejournal.com]

one thing i learned from when we first moved here 5 years ago, was that you have to make sure that all the radiators are turned on. if one radiator is turned off, the whole system gets off kilter and the banging pipes start. i tried to do this because i was used to european radiators, where i would turn it on when i entered the room, and the rooms that weren't used were left off. so maybe check to see whether all of the knobs are turned on?

[mindstalk.livejournal.com]

I see. Probably steam, then. There's just four feet and a pipe with the control valve, and an opposite valve that hisses. Childhood radiators didn't have that, but had something you could key to let air out until water came.

[mindstalk.livejournal.com]

I would guess that means all radiators in the large apartment building, which, oops. I have usually kept two of my own radiators off, since with the naked pipes I don't even need the radiators! There's a third one I can't turn off though.

[unferth.livejournal.com]

Yeah, those sound like single pipe steam radiators. Unsurprisingly; they're pretty common in old houses around here.

The keys to let air out are just for hot water radiators. Ideally, liquid water should never leave your steam radiators.

This post seems like a pretty good summary of common problems and what you can do about them - not much, if it's your neighbors radiators causing it.
http://www.yrgxyz.com/yrg-blog/test-blog-post-2/

[emcicle.livejournal.com]

We just moved into a house with steam pipe radiators. and man, the banging has been really hard to get used to. Something that has helped us was to insulate the pipes in the basement. We also made sure all the radiators were pitched correctly (they should all tilt back a little (3-7% I think was the range) back towards the entry pipe (where steam enters from) so that the condensed water can run back into the system. We used a level and some quarter sized piece of wood my husband cut out to tilt them. Those two things have helped significantly, but not completely. I would also recommend "the Lost Art of Steam Heating" (more technical) or "We've got steam heat" (more, i live in an apartment with steam heat oriented) by Daniel Holohan (you can get it at the library). He also has a website, heatinghelp.com and the message board called "the wall". Of course, if your landlord isn't receptive to doing anything, I'm not sure much of this will help.

[aislingk15.livejournal.com]

I recently had someone come to fix a number of problems with my steam radiators, and while some of the issues did turn out to be with the rads, it also turned out that the boiler itself was making terrible banging noises. The water in the boiler was really dirty, and needed to be skimmed. (If you have access to the boiler, you should be able to see the color of the water in a glass tube on the side.) Once the dirty water was skimmed off, the noise was gone.

I'm a relatively new homeowner and so I'm just learning about these things, but I don't think the "it's old so it's noisy" line is the final word.

[bombardiette.livejournal.com]

I sympathize and have no useful solution. Our pipes don't bank but our radiators whistle like tea kettles and hiss so loudly it's impossible to hear anything when the heat's on. The bleeder valves have all been painted shut and and the thingys on them to release excess are all new. I'm resigned to it. :(

[cfox.livejournal.com]

We leave some of ours turned off, to balance which rooms get how much heat; I don't think turning radiators off is necessarily a problem, as long as some of them stay on to provide a place for the steam to go. That said, I don't go messing with the settings every day.

A really big cause of knocking is the angles getting too close to level, for either radiators or return pipes. Sometimes someone clueless sees the radiator looking askew and "fixes" that (they're supposed to sit at an angle) and sometimes it's the house sagging around the radiator/pipe. (Also, a radiator that develops a hairline crack and a slow leak may accelerate the process of the floor warping around it.) You can probably shim up a radiator that's too level, yourself, but it might get expensive to deal with a long horizontal pipe (sometimes adding a dedicated return pipe for part of the system is the mitigation strategy).

My house also has some banging caused by a pipe that's long enough that thermal expansion causes several inches of motion in one end. This sounds like you dropped something really big and heavy, in a predictable spot, which is distinctively different from the messed-up water-return noises.

[boblothrope.livejournal.com]

That's not true. A well-designed steam system can have some of the radiators turned off.

In fact, a modern retrofit which I highly recommend is thermostatic radiator valves. They're those knobs on the radiator input pipe numbered 1 through 5, plus a snowflake setting. They automatically turn each individual radiator off when the room temperature rises above a certain level.

They're the best way to keep your house a comfortable temperature, and save a whole lot of energy in the process. (No more opening the windows when it's 20 degrees outside because the heat is too hot!)