One-Pipe Steam Boiler Replacement

Lyle_2

I'm in the NW corner of CT.

Lyle_2

One-Pipe Steam Boiler Replacement

Dear Wall,

I've recently finished reading "The Lost Art...". It's an outstanding book and highly recommend it for all homeowner's with steam systems. I'm sorry I hadn't read it prior to last year's boiler replacement.

I have some remaining concerns and questions about my system that I hope you can answer for me. Could you please review the attached files and respond with your unbiased, professional opinion.

Please let me know if you have any questions.

Thanks for your help!

Lyle Kloke

John@Reliable_14

Proper burner set-up ,skimming ,along with new sized main vents will go a long way improving system comfort and fuel usage.I think the hard part will be finding someone who understands what I'm talking about, where are you located?

Paul Fredricks_9

I agree with John. To be honest, I stopped reading half way through your PDF. Instead of relocating the main vents, you could offset them. I think that is cover in Lost Art. Not perfect, but quite a bit easier.

The asbestos looks like some has been removed, and some pipes are left uninsulated, they should all be insulated with 1" think fiberglass pipe insulation.

The equalizer is fine at the 45.

No swing joint on the top of the riser. Not sure that is a horrible thing. Would have been better with, but I don't know if there is that much stress on the boiler with just one riser.

All of this in my opinion. There are many here that know more than I do.

Kool Rod

Hi Lyle-
I agree with Paul. You rather overloaded us with information. Probably the best thing to do is to address one or two issues at a time.

Main vents- After a quick look, as Paul said, your main vents appear to be too small. I've attached a great drawing done by Brad White on "Menorah /Antler" vents. Note the pipe union. This allows you do to make /service the vents on a bench and then use just one connection. Makes it much easier than standing on a ladder, working in the tight confines between floor joists.

The idea of main venting is to evacuate air from the steam mains as quickly as possible. You should use as minimum of a single Gorton # 2 and many people use multiple Gorton #2s.
Here a good link for you to Gerry Gill's website. Lot's of good information. Note the pictures of multiple vents.

http://www.gwgillplumbingandheating.com/

Gerry and Steve wrote the book on venting -

http://www.heatinghelp.com/shopcart/product.cfm?category=2-138

Pressure Gauge- Your steam pressure appears to be set slightly high. It should be as low as possible. Below 2 psi max and most people run their systems at under 1 psi max.
The pressure may have been set high to overcome the undersized vents. More pressure = more fuel used.

You will need to get a lower reading pressure gauge than the one that comes with the boiler. I'm using a 33020 (0-3PSI)from the Gauge Store.

http://www.gaugestore.com/products.asp?dept=1123

For insurance/code purposes you are required to have /leave the original gauge (0-30 PSI)installed so just branch the new gauge off to one side using a tee, elbow etc. I'd use brass fittings as they are less likely to corrode. The gauges and pressuretrol must have a "pigtail" to protect them from the steam.

Skimming- You might want to use the "search" function on this site as there are a lot of good past posts on skimming.
Generally it seems most people aren't into using additives in the boiler water. Besides having a proper PH it is also important to bring your boiler water to a boil, after you have added water, to drive off the excess oxygen which can form corrosive solutions if it isn't boiled off. (I mention this as you may be doing flushing/filling/skimming)

At a glance, some of your piping appears on the small side but I leave the experts to comment on that. I might suggest that it would probably be well worth your while to have a good steam pro take a look at your system. Go to "Resources" at the top of this page and click on "Find a Professional" and see if someone is listed in your area.

- Rod

Lyle_2

Sorry for the info overload. I thought it was best to give it all in one shot rather than piece-meal. My only goal is to determine what needs to be corrected and get it done before the next heating season starts.

All my work has been done by a local company that's been around for a hundred years. There are others in my area that I could try, too. In either case, I'd like to know how things should be done properly beforehand instead of after the fact.

Again, thanks for any help you can provide!

Lyle

Kool Rod

Lyle- I had more time this evening to look over your pdfs and pictures. My impression is that you're getting a bit too much into the details of the ideal steam system and are over complicating things. What I think you probably need to do is figure out what is working satisfactorily and what isn't and just concentrate on fixing the "isn'ts".

Basically you can break your steam system down to four sections: Boiler and boiler piping, Mains, Radiators , Returns. I'd just address each section individually.

Boiler- From what I can see fro your pictures your boiler piping is generally satisfactory. It might not be perfectly to "LASH" specifications but again the criteria is "Does it work properly?"

Swing Joints- These are nice to have but you don't see them used much. In your case, on your boiler you have only one exit riser from the boiler so the lack of a swing joint isn't that big a problem. If you had two exit risers then it would be important to use swing joints as the expansion of the pipe between the exit risers would put force on the boiler castings.

Close Nipple on the Wet Return / Hartford Loop connection.
Yes, this should be a close nipple. You see "Y" specified on drawings but I don't think I've ever seen one used, mostly it is a 90 degree elbow and a close nipple/tee. The question here is: Does the short nipple now installed causing a problem? If so then it needs to be changed.

I mentioned a having good low scale pressure gauge in my previous post. This is pretty necessary if you want to get your pressure down to the minimum. You may also need a vaporstat as pressuretrols get "squirrelly" at really low pressures (under 1 psi)

Skimming - I also mentioned that you should look up past posts on skimming. To get the boiler water`right you may have to do multiple skimming. The last time I skimmed I skimmed for 2 hours each on 3 consecutive Saturdays. You have to have good boiler water to make good steam!

I see you have a VXT-120. They're a good unit. If you haven't already done so you might want to read up on its operation and setup.

Pigtails- Check them annually as they can get corroded and the opening restricted. I use a bronze one as they seem to resist corrosion better.

Mains- You mention the first section of your mains slope back towards the riser that come out of the boiler. While this isn't ideal, many systems are counterflow and the condensate returns to the boiler this way. I think the criteria here again - Is it causing a problem?

On the mains the idea is to get the air to evacuate as quickly as possible so the steam can fill the mains and then enter the radiators.
I believe you mentioned that the radiators get steam/heated first and then finally the vents. It should be the other way around. The main vents heat first and close and then the radiators get steam. You need to time how long it takes for steam to get to the different parts of the system. The idea is to then make adjustments to minimize these times. You then will soon see what changes are advantageous and what ones are not. If you don't have it already you might want to get Gery Gill's booklet on Venting. I gave you a link on my previous post. It has a lot of info on vents and venting.

Insulation - The mains and near boiler piping should be insulated. The idea is to get the steam straight to the radiators. Proper insulation makes a big difference. 2 inches is ideal however from an economical standpoint 1 inch gives you the biggest bang for the money. After that the efficiency increase is much smaller. Insulating exposed pipes between floors is more of an aesthetic question. Does your wife like the look of fiberglass in her living room? Most people just leave them bare.

Radiators- You've already mentioned having to have the necessary slope. You are also probably going to want to replace all your radiator vents. They only last a few years and if they have been exposed to high pressure over 2 PSI they are probably thrashed.
TRVs- TRVs only control overheating. On a 1 pipe steam system you must use a special TRV made for 1 Pipe steam as these have a vacuum breaker. I've found TRVs very beneficial when you want to close off section of the house during cold weather. Most TRVs have a minimum setting (about 42 degrees) which keeps the closed rooms from freezing.

Piping to the radiators - Again first ask yourself is the radiator working okay? I've seen radiators grotesquely piped and would have bet money that no way they would work and I would have lost my money. The old adage: "If it isn't broke, Don't fix it!" is the watch word here!

On the 2 pipe radiator you'll need a trap or a loop to make it work properly.

One thing you didn't mention is what type of thermostat you are using on your boiler. For steam you must use one where the number of hourly cycles can be set. This can save a LOT of fuel! Most of the setbacks types from Lowes /Home Depot don't have this. Also generally it is felt that using a setback of more than 5 to 7 degrees is economically counter productive due to the long "catch up" time.

When you post future questions, I would suggest is that you break your questions down to an item at a time. The guys on here are great about answering questions though being busy, they only have usually have time for a sentence or two in reply. Phrasing is also important. For an example: On the question you asked about the chimney pipe draft. Ask something like: "Please take a look at the chimney piping and comment." Attach the photos and maybe the combustion readout. This is a burner question. Since you originally included this in a "steam question" the hotwater guys (The "Wetheads") probably wouldn't take a look at it and therefore you'd be missing a lot of good input.


Hope this has answered some of your questions.

- Rod

Jamie Hall

Where exactly

in northwestern Connecticut? I am not a pro (I'm a building superintendent near Winsted), butI have a good deal of experience with steam systems and would be happy to help you out some. Send me an e-mail direct if you like.

Lyle_2

Rod,

Thanks for taking the time to review my concerns and to respond with your suggestions. I definitely want to focus on what is most cost-effective without worrying about details that have little, if any, impact on the system's operation.

As long as piping is not an issue, I can proceed with insulation repair and replacement.

I had ordered the Venting guide last Friday and am waiting for its delivery by email. I believe the "antler" show in your drawing will work well.

T-stat is a LuxPro 511 series programmed with a 4 degree setback morning/evening and 2 degree swing differential. No hourly cycle setting- Something else I'll need to look into. (Last season, only 1, maybe 2, cycles per hour. On and Off)

I had previously gone over the VXT-120 information and fill-time procedure. Current setting: 1 minute (1 gal) fill time, 2 minute delay. Water use has been minimal, at most a couple gallons for the whole season, not the 10 per month the instructions say is allowable.

Thanks again. You've all been a big help.