Steam newbie questions

barold10

My wife and I bought our first house last fall.  After a winter of outrageous heat bills we decided to do some self-educating.  First we thought if we put a new furnace in it would save on our bill.  Well it turns out we didn't even have a furnace in the first place.  We have a steam boiler.  Which after researching this website and poring over Dan's We Got Steam Heat we learned we have a one pipe system.  A little knowledge is a dangerous thing!



I've already lessened the setback to 2-4 degrees, turned down the pressure, insulated the mains, had the boiler serviced - pigtail and burners cleaned etc, but it still takes too long for the radiators to heat up. 



We have 2 mains 2.5in thick with one ~25 ft long the other ~15 ft.  Not sure if it matters but the 25ft section only has 2 radiators while the shorter one has 4.  The venting - 2 Gorton no. 1's - are on the dry return right before it drops down back to the boiler.  I've also noticed the near-boiler piping is incorrect.  If I'm using the proper terminology the header is between the two risers instead of after.



I'd like to get somebody to take a look but using the find a pro link on this website there isn't a pro within 30 miles.



My questions are... Does anybody know a reputable steam pro in the New Brunswick, NJ area?    Would changing the near boiler piping be expensive?  And more importantly worthwhile?  And also is the venting adequate?  Does it matter where they are located?



If you've made it this far thanks!

-Brian

brian_44

Similar situation I had...

You should post pictures of your near boiler piping here for others who are skilled to comment. Make sure you get the piping over the boiler as well as the returns and the area where your hartford loop is.



The fact your venting is all near the boiler might be a part of your issue. That's how they used to do it. In my case, it was inaccessible to me to add main vents so I used the vari-valve vents on my radiators that were slow to heat up. It's all about getting the air outta there as fast as possible (as you know from Dan's books). While some here don't necessarily like the vari-valve vents (and I don't use them throughout the house), they worked in my scenrio anyway... What kind of venting do you have on your radiators? Good vents are a great investment.

Jamie Hall

It sounds...

as though you are certainly on the right track!  Further, it sounds as though you have a parallel flow system -- that is, the mains slope down away from the boiler, and then come back -- still sloping down -- to the boiler and then drop down to the boiler wet return.  For a parallel flow system like that, it really isn't necessary that there be vents on the ends of the mains; the vents you have are in a perfectly good location to do the job.  Whether they are adequate or not is another matter; there are resources on this site to help in vent sizing (I don't have the link handy right now).  More venting is almost never a bad thing!



With regard to the time it takes the radiators to heat up, keep in mind that steam is not like hot air, and doesn't respond as quickly!  What is important, though, is how evenly steam is distributed to the radiators, and how quickly they warm up after the boiler starts to make steam.  So... what you do is sometime when the boiler comes on, go down there and wait for steam to appear in the header.  Then hop about the house and see how long it takes from then for steam to get to the various radiators -- it should be pretty much the same for all of them, and it should be only a few minutes.



It does sound as though you have near boiler piping problems.  These can make a big difference in evenness, speed, silence -- and money.  Without looking at the pictures, though, one really wouldn't want to say how much of a hassle fixing the piping might be.  Could be easy.  Could also be a bear.



As to a pro, when you check the "Find a Contractor" section, be sure to search by state, not zip -- and check New York and Pennsylvania as well as New Jersey.

BobC

High bills

Your 25 ft 2-1/2" main has about 1.5 cu ft of air in it and a gorton #1 is good for about 0.5 cu ft per minute. It really should be a Gorton #2 on that long main while the #1 is probably a bit shy on the 15 ft main (about 1 cu ft). If you did replace the vent on the long main you could put the #1 onto the sort main with the existing one using an antler.



However if that 2-1/2" is the outside diameter of the pipe then it is a 2" pipe (2.38" OD) so in that case 25 ft of 2" main has 0.94 cu ft and the Gorton #1 is probably ok on that long main for now. More would be nice but that is not your main problem.



With the near boiler configured as you said you are making wet steam which is not good for efficiency. That configuration causes water to be drawn up into the header and possibly the mains as well. What pressure are you running at, it should be under 2 PSI.



Post some pics so we can see what your dealing with.



Do you know how long it takes things to get up to temperature from a cold start? The attached file shows how my system is working (still a work in progress), see if your system numbers are anything like this. Also note how long, after the steam main is hot, it takes for the radiators to get hot and which radiators take the longest. Also what size are the radiators and what vents are on them?



good luck,



Bob

The Steam Whisperer (Formerly Boilerpro)

Find A pro....

A number of pros travel further than 30 miles.  I have traveled over 300 miles each way as a consultant.



It sounds like your on your way.   Have you overfilled the boiler with water to see if there is a leak above the water line.  These are sneaky, becasue wated does not show up on the floor, the fuel bills skyrocket, and there is little heat for upstairs.

Many properly sized boilers will take 10 to 20 mintutes before any substancial amount of heat may show up at ratiators.

barold10

thanks

Thanks for the many quick responses.  This site is an excellent resource.  I wish I had discovered it last year.



I took some pictures of the boiler piping.  And since it kicked on while I was down there I timed it as well.



It took about 6min for the start of the main to get hot and 25 min for all the radiators to get hot all the way thru.  After 43 min it cycled off.  From what some of you posted it seems within range.  I may just never have noticed because before this house I always rented.  My previous place had steam but it would get so hot I'd have to open the windows.  And that was in Boston.



The pressure gauge didn't move the entire time.  I have the pressuretrol set to .5 cut in and 1 diff.  Now the gauge is 0-30 so it might not be sensitive enough to register.



Thanks again!

Brian

Rod

Boiler Piping Configuration Problems

Hi Brian-  You have problems with your near boiler piping configuration.  On your boiler the boiler risers are split by the riser to the steam

main so steam streams collide and suck condensate (water) up into the

main resulting in "wet steam" which isn't efficient. I 've attached a

diagram on this. The whole purpose of the header pipe is to separate water from the steam. The header pipe should have a slight slope towards the equalizer and the sequence of piping connections to the header should be boiler riser pipes, risers to the mains and then the equalizer pipe.



Header pipe- The header pipe should be a size or more bigger then the boiler risers. This slows the velocity of the steam down which results in more water precipitating out of the steam stream. Since you mentioned you have two steam mains, ideally each main should have its own individual riser pipe connecting it to the header. Ideally you should use a "dropheader" as they produce much dryer steam.

- Rod

Mark N

Run Times

Brian



You state that rads are hot all the way through after 25 mins. I would think the tstat should have been satisfied then, and not ran the boiler another 18 mins. I've observed how my systems operates over the years. I set my tstat for 70 and leave it. The boiler runs between 20 to 25 minutes and shuts down. Rads are about half hot and the house is comfortable no rooms to hot and none too cold. You have a small system like me, these system can be very economical to run. Look into getting your near boiler piping fixed. Insulate all you piping if it not insulated. I would look to see if your tstat is set up properly. If it is a digital is it set to 1cph or if is the old mercury type is the anticipator set right. Also tstat location is important if it in a location subject to a draft it can run the boiler longer than needed.



Mark

barold10

t-stat and dropheader

Mark,



The t-stat is in a hallway on an interior wall.  Its a programmable digital type.  There's no cph only a swing adjustment.  The swing adjustment runs from 1-9.  Its currently at 4.  Not sure what it should be set at.  I guess I can fiddle and find what works best.  Or would I be better served just replacing it?  Now that theres no setback the current tstat seems unnecessary.





Rod,



Thanks for the diagram.  What makes wet steam less efficient?  Is the water just clogging the steam artery?  Also what's a dropheader? 

Mark N

Boiler Issues

Brian



Do you have a manual on your tstat? If not see if you can find one one the internet. Its hard to say if your making wet steam or not. You have 2 risers from the boiler then that riser up to main looks quite high. I doubt any water is getting into your mains. Water mixed in with the steam robs the steam of its latent heat BTUs. Does your water level drop below the bottom of the sight glass when the boiler is running? From what you stated in your early post your boiler is getting your rads hot in 20 something minutes. If the tstat would turn the boiler off then it would save money. The less time your boiler runs to heat your house the gas you burn. Try placing a thermometer where your tstat is located to check how accurate it is. Are your rooms overheating from your boiler running to long?



Mark



Mark

Jamie Hall

drop header and wet steam

a drop header is a nifty way to really improve steam quality.  In a drop header installation, the riser(s) go up in the usual way, typically 24 inches or so.  Then they go horizontally (almost) a bit of a ways, then drop down to the actual header -- the drop is often as much as will fit on top of the boiler.  Then the connections to the system come off the other end, as it were, of the header, and the equalizer drop is at the far end.  Any water drops that can make it through that are pretty determined...



As to why is wet steam a problem -- first, any of the water drops that are carried along have to continue to be carried along -- to the first drip or whatever.  And if there are enough of them, they can impeded steam flow or cause nasty water hammer, all though a boiler cycle.  Second, though, has to do with the thermodynamics of wet steam -- the presence of water will assist the steam to condense further, and release its heat right there in the main, rather than in the radiator where you want it.  Very inefficient.

Rod

Dropheaders

Hi- Here a link to some good pictures of dropheaders. http://www.heatinghelp.com/files/articles/1348/127.pdf

- Rod

Johnny13

I am going to piggieback on this thread, and hope it is not rude.

I need to hook up a radiator myself for the first time. Do I need to dope the connection, or can I use Teflon tape? I know the pressure is not great, but I am assuming I need something there to help the seal.

barold10

I think I'm sorting this out finally...

Mark,



I found the manual online.  The tstat is from the previous owner and I'm not sure its for a steam system.  There's no cph just swing.  The higher the swing number the fewer cycles per hour.  So I upped it to its highest swing setting.  I'm gonna have to get a thermometer to ensure its giving the correct temperature.  Tomorrow I'll see if this swing setting makes a difference first.





Jaime & Rod,



Thanks for the info.  I'm going to call one of the pros listed on here and have him come in and see if he can drop in a dropheader.

BobC

tape or dope?

You can use pipe dope or teflon tape, you have to use one or the other (some use both) on that big nut  to make it a steam tight connection AND make it possible to separate the joint in a decade or two without to much cursing. Just make sure the pipe/valve line up squarely with the radiator and put a light coat of pipe dope on the mating sufaces of the valve and radiator to ensure a tight seal.



Bob