Noise Issue with Steam Heat

savageblu

I have a gas-fired one pipe steam boiler in a 2 story single home. When the heat comes on at the beginning of the winter all the radiators are quiet as is the whole system. But as time progresses it starts getting noisier and noisier, especially the vent valve in the upstairs bathroom radiator. All the valves in my home are less than two years old. Does anyone know why this might be happenning?

Jamie Hall

What pressure is the boiler being allowed to run at? Sounds like it may be too high.

jhewings

You may have inadequate or even non-functioning main vents in the basement and/or your steam pressure might be too high. The pressure should never get above 2 psi for 1-pipe steam. I also found some cheaper radiator vents were noisier than the "upgrade" vents I have now but look at the other two things first.

savageblu

I only know of one main vent in my system, which I replaced a few years ago with a good quality one. Do you think that there's more than 1 main vent in my system? As far as my pressure goes, it never reaches above 2 psi and is normally 1 or lower.

neilc

post a picture or 2,
of the boiler, floor to ceiling,
we need to see all the pipes up to the ceiling, all in one,
and maybe a closeup of the boiler controls

savageblu

The boiler never runs higher than 2 psi, and mostly stays around 1 psi or below. I'm going away for a few days and will send the photos you requested when I get back, either Sunday or Monday. Thanks for the help.

savageblu

The main vent is not very old and seems to be working fine, and as I mentioned in my first post, the pressure never goes beyond 2 psi and usually is under 1 psi.

According to Dan Holohan you're supposed to put the vents with the larger holes (highest numbers?) in the larger radiators and the vents with the smaller holes (lower numbers?) in the smaller radiators. But I and many others always were told to put the vents with the larger holes in the radiators furthest from the boiler and vents with the smallest holes in the radiators closest. Based on this "theory," I put a Gorton #6 in the radiator in my upstairs bathroom, which is the one that makes the most noise from the vent valve. But if Holohan is right then perhaps my problem is that the vent valve is too large and I need to use a smaller number one in that bathroom? I'm very confused about all this and just want my radiator in the upstairs bathroom to stop hissing and the whole system to quiet down (again, right now the system is quiet but as the winter wears on, it gets noisier and noisier.

mattmia2

It is both. More piping between the radiator and boiler means more air to vent (much will vent out the main vent but there will be runouts and risers that have to vent through the radiators). A bigger radiator has more air to vent. That is a starting point but getting the rooms all the same temp will take some tweaking, putting smaller vents on hot rooms or bigger vents on cold rooms. There will be some
difference in how well the radiator size matches the heat loss of the room too.

Did you try a new vent? Poor quality vents are also a possibility.

savageblu

I couldn't find any #2 or #3 valves so I just ordered a varivalve and should receive it tomorrow. But I won't know if this solved my problem right away, since the valve only gets noisy (steam hissing) as the winter wears on. In the beginning when I first turn on my heat, it's quiet like the others. Thanks for the helpful advice about how to balance the vents and I'll let you know if the new vent worked in a month or two.

neilc

I'm not a venting expert, but I think I just read in another thread that the varivents are rather fast, hard to adjust vents, hard to adjust down to slow enough , , ,
and if you're having noise or spitting issues, you're going to want a slower vent,