Single Pipe Steam Radiator Hissing

Pinec0ne

I recently purchased a 1920’s home and replaced the steam boiler. I just had the lined cleaned to prep for the upcoming cold months in NJ. I love the heat but I can’t stand the noises. I’m a super light sleeper and get woken up in the middle of the night whenever the heat turns on by whirring, whistling, whooshing, hissing, etc. you get the point. I would like to get to a state where the radiators are silent, is that a realistic expectation? Should the air passing through the vents make this level of noise? 

I need regular sleep. Earlier this year I added ac ducts and chose against doing forced heat. Now I’m slightly regretting it with the constant sounds, but if I can eliminate them I know I made the right choice. 

dabrakeman

Proper working system should be silent or nearly so but more info is needed. 

Do your noises occur every heating cycle?  Are you trying to do big temperature recoveries in the morning...?  First steps are to 1) understand what pressures your system is running at.  Send a picture of your pressuretrol settings and also take a look at your pressure gage when you notice the hissing.  2)Do you have adequate main venting on the system?  Take some pictures of the boiler and near boiler piping from various angles and share them.  Find your main vents and tell us what you have or take photos of them and share.  3)  Are you venting the offending radiators too fast?  What do you have for radiator vents on those radiators.

Generally hissing/whirring noises are indicative of too high operating pressures, wet steam or venting too quickly. Lots of causes for too high operating pressures and wet steam so need a better overall understanding of what your system is in terms of size of the boiler vs total edr of all the connected radiators, near boiler piping configuration and main venting.

AdmiralYoda

Like @dabrakeman said, steam heat should be one of the quietest heating systems possible. Certainty quieter than scorched air or forced hot water baseboard.

My home was similar to yours when I moved in. ZERO main vents so the radiators did all the venting. Hisses/whistling until the air was forced out followed by the air vent slamming shut with a "clang". Over and over. My pressure was also higher than it needed to be. I've remedied that and most of the time I don't even know when its on.

We need to understand your system better. Basically everything that @dabrakeman asked.... Pictures help!

Pinec0ne

Thank you both for the feedback. This is very promising to hear that it should be dead silent. I will review when I get home and get back to you. I’ll give a list of all radiators, steam boiler, and pictures to match. 

neilc

yeah, pictures, we're gonna need pictures,
post a picture of a typical radiator, and a distant shot showing us where it is, both ends,
might as well post a picture or 2 at the boiler,
show the controls, sightglass,
and a more distant shot or 2, floor to ceiling, so we see all the piping above and around the boiler,
has the pigtail been serviced? are you blowing down the low water cutoff? is the water dirty?

JohnNY

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Pinec0ne

I will preface this reply by saying that I had posted my system in the past and the community advised me that there were some issues not to spec. I had already paid and had not gotten these installation issues addressed, but did have local plumbers come and tell me it should be fine. 

Pictures appeared to upload out of sequence

Notes

• House layout is a multifamily with floor one being one unit and the second floor and finished attic being another unit, the one in which I reside 
• radiator 1 - finished attic, hisses, good heat, just repainted and had risers installed, no other issues
• Radiator 2 - finished attic, hisses, good heat, just repainted and had risers installed, no other issues 
• Radiator 3 - 2nd floor, hisses, water drips at the spud, heats up well, up shoot goes to radiator 1
• Radiator 4 - 2nd floor, does not get hot, seems to be leaking slightly at riser connection, makes banging sound when closed and heat is on. 
• Radiator 5 - second floor, does not get hot, does not hiss, also leaks a bit at riser connection, up shoot gets hot and goes to radiator 2.
• Radiator 6 - 2nd floor, hisses, gets hot, connection appears to be taped up, and thus likely leaks
• Radiator 7 - 2nd floor bathroom. Hisses, gets hot, no other visible issues. Will be removing this when I remodel bathroom 
• System - Utica Heat UH112ESTM4SNATHWUH 112 KBTU, installed in April of this year
• Pressure on system with heat off was 1 psi, should I measure this with heat on? I assume so
• Water was cleaned and flushed last week

JohnNY

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JohnNY

Pinec0ne said:

I will preface this reply by saying that I had posted my system in the past and the community advised me that there were some issues not to spec. I had already paid and had not gotten these installation issues addressed, but did have local plumbers come and tell me it should be fine.

Which local plumbers? The ones that installed that boiler? Left as it is, it isn't going to be fine. It's going to keep on being what it is and it's going to keep doing what it's doing.

Jamie Hall

Take the easy one first: those internal siphon gauges are there because the insurance companies and building codes require a gauge which reads to twice the pressure relief valve setting. They are notoriously inaccurate at low pressures (your 1 psi reading is inaccurate -- it should be zero -- but not too bad...). You should get, and install, another low pressure gauge to see what the boiler is really doing. It can go on the same pigtail as the pressure control, using a T and a few odd fittings.

I can't read the setting on the pressure control, but it should be set to cutin at just above half a pound -- probably about as low as it can go, and cutout at 1.5 pound.

Now. I'm not at all sure I've ever seen the near boiler piping arranged quite like yours. Not saying it won't work -- strange things do with steam -- but it seems unlikely that you are getting even remotely dry steam out of it. You might see if you have the installation manual around -- the installer should have left it -- and compare your piping to the minimum the manufacturer wants. Failing that, if we have the make and model we may be able to find the manual for it.

As to the assorted leaks. Most likely most of them are either misaligned unions (or damaged ones) or worn packing on the valves. Not hard to repair, in most cases, but damaged unions are a problem.

While valves placed horizontally is certainly not best practice -- it can lead to hammering -- they can work, if they are fully open. If they aren't hammering, not to worry.

If a one pipe steam radiator doesn't heat, or heats very poorly, there aren't that many things that can be amiss -- it's pretty simple. The air and condensate have to be able to get out freely, and the steam has to be able to get in. This is one area, however, where a horizontal valve can create trouble: it may not be open, even if it looks like it is, and prevent the condensate from leaving. You can also have a faulty vent.

mattmia2

Your near boiler piping is very wrong, it isn't going to work right until you fix that. There are lots of part that are wrong but the worst part is coming horizontally instead of vertically out of the tapings. the water that is carried out with the steam will collect in those horizontal sections then the steam will both propel the water in to the mains and it will collapse some of the steam. The system won't work well until the boiler is piped properly.

The leaks at the valves are minor fixes that would have been included in their quote by anyone competent replacing the boiler because those leaks will eventually damage the new boiler with the fresh water they cause to be added to the system.

neilc

yeah, that's a lot of spagetti pipe around that boiler, hard to be sure what's going where,
I think I see counterflow drips, with vents right above the drips, those vents will see steam too soon, and close.
the mains should be at the far ends of the mains so air is vented all the way to the far ends,

the Ptrol looks to be set rather high, maybe to overcome the bad vent locations, ??
dial the Ptrol down as low as it can go, and still reliably restart, cut back in,
this is your hissing, and spitty vents,

as others have said, the near boiler pipes are wrong, but it's hard to decipher from that distant picture,
post another 2 pictures from the top of the boiler to the ceiling, 2 different angles,