Wet Steam Vs Dry Steam:

icesailor

I'm not a Steamer and there isn't much steam where I work. I was asked to get a large combo oil and gas burner going that had stopped running. I got it running and when looking around, the boiler appears to have a lot of "issues". Like the water feeder/LWCO is fed with a 1/2" Watts 9-11 combo back-flow and boiler PRV. The boiler kept going off on low water because the steam pressure was higher than the setting on the 1156 PRV, The problems are too numerous to list here. I'm there because I have a MA pipe-fitters license and the boiler is over 400,000 BTU's.

From what I have learned here about the requirement to follow the manufacturers piping diagrams. At first glance, it isn't even close.  The piping off the top of the boiler rises straight up into a large header. No 90 degree offset. An equalizer pipe rises off the top of the header and drops down into a pipe that runs from the ends of the boiler and into a connection in the middle of the equalizer and boiler. The connection of the return I never really got into my memory. But rather than the steam going into the system in a vertical position, runs out of the end. So that this becomes an extension of the steam collector that runs into another room and the take off's to the equipment comes off the top. There is a return on the bottom of the large header that drains into a condensate pump/tank.



Does something like this make for wet steam or dry? Or am I looking at something that isn't there? This system was supposedly designed by a Professional Engineer/Steam Expert and installed by a steam expert.

The owners claim the system has never run better since I worked on it. I don't want to start problems for anyone. These guys have worked their butts off in this business. But someone has a mess on their hands.

I got the oil part running like a champ. The gas side has never run. I figured out that the burner was ordered wrong (not by the owner) and ordered and set up for natural gas. It is run on LP and there will NEVER be natural gas. The size of the output and the LP tank area make me believe that the liquid will never boil into gas in cold weather due to not enough surface area. I ordered the conversion kit, I will install it but I'm not going to fire it. Someone else can do that.

Rod

Major League Steam

This is obviously a question for the pros. Any chance of getting some pictures of the piping as I'm sure that would be of help to them.

- Rod

icesailor

Photo's:

That is hard to do. And I'd prefer to not plaster photos all over the world for all to see. My goal if it is attainable is to quietly resolve regulatory issues. The system seems to be working OK for what it is being used for.

I did work like this back when I worked for my (late) old boss. Right or wrong. We always did it right, as we understood it. When I look at something like this, and although I haven't dealt with a personal install like this, I could have or would have. But I wasn't asked. I get asked to fix things. A much more interesting challenge.

When I see things on something that I KNOW are wrong and other things that I'm quite sure that are wrong, I start wondering what else is wrong. I remember reading that boilers over a certain size can't be vented with 24 gauge galvanized smoke pipe. That it is supposed to be thicker and welded. The gas for the pilot is piped upstream of the main shut off so if you shut off the gas supply, it is still live to the pilot. I'm quite sure that in MA, you can not use a compression fitting on a gas line, feeding the appliance, even if the manufacturer supplies it. It must be flare. The compression fitting was leaking gas.

There's no separate by-pass water feed. All make up water goes through the M-M LWC, with a 9-11 feeding the whole mess. It isn't a hot water boiler, it is a steam boiler. The cold water feed enters in this "equalizer" pipe that may or may not connect into the system side of the boiler. I'd have to look. As I think on the whole thing, I get more questions. I just want to quietly, if possible, resolve issues.

I'd compare the application to a ten wheel tractor that has the power to tow a triple rig trailer set up down the interstate. Only, it is towing my single axle, 1200# rated boat trailer, towing my iceboat that weighs 50#.

I'm just looking for answers.

icesailor

Dreying Out The Steam

I found answers to my questions, here:



http://www.spiraxsarco.com/resources/steam-engineering-tutorials/the-boiler-house/steam-headers-and-off-takes.asp



It's not done to accepted steam piping practices.

Like most things hydronics, it will work. Like shopping at Sears. They offer, Good, Better and Best.

Good is acceptable for some, Best is the best and acceptable for some. I always try to go for the best, and hope for the best.

gennady

STEAM PIPING

you have to follow manufacturer recommended piping arrangement to the letter. harford loop is a must on steam boiler, or you have to use steam separator, to remove water from steam. Steam leaving boiler always has carry over water in it, and this water must be removed.

icesailor

Steam Boiler:

Gennady,

I didn't design or install this boiler. I only went to work on it because an electrician friend asked me to see if I could get it to run. It has been running for a few years. It had a burner problem. I was there for the burner problem. It needed a new 7800 Honeywell controller. I looked at the boiler and couldn't figure out if it was a hot water or steam boiler. I've piped a few steam boilers back when and I've worked on a few but I had never seen anything that looked like this. I once was sent to get a new steam boiler to work in a Post Office. I found a brand new Smith-Mills 2000 series 7 section boiler, installed as a forced hot water boiler (with no circulators) on a one pipe steam system. It didn't work. It had been installed by an AC contractor. I see it all.

But back to the subject at hand, For example, once the boiler started making steam, it was shutting off for no apparant reason to the ownerr, It always did. The boiler was filling to the M&M feeder and LWC. The Feeder was fed water by a hydronic Watts 9-11 PRV feeder. The 1156 was set for a pressure that was lower than the operating pressure of the boiler. When the water level dropped below the float, it couldn't fill because the boiler pressure was higher than the fill setting on the PRV. There was no feed by-pass on the M&M. You couldn't add water to the boiler until I raised the PRV pressure. The cold water feed from Potable water should have been installed by a licensed plumber. It was connected by someone without a pipefitters license (that didn't matter) and did not have a plumbing license, that does.

From what I have read here and elsewhere, the function of turning after leaving the boiler is to "wring" out the water from the steam. That everything in the piping is to try to dry out the steam to the greatest level. In no way does this remotely follow this rule. I wasn't asked to diagnose the piping. I was asked to make the burner run. The oil part wasn't running and now it is. The gas part doesn't run according to the owner. No wonder. It was built for Natural Gas, not LPG which it is fired with. It was never converted from Nat. Gas to Propane.

I'm going from memory. I didn't take pictures.