wide open 1/2" pipe

steam-rookie

I have replaced my main vent with a 2" pipe and ball valve

It takes 8 min. for the steam to start its journey

It takes an additional 18 min. for it to reach the open ball valve at the end of the main.

That is not 25 mph.

Why is it taking 18 min. for the steam to travel through a 2" pipe that is 100 feet long?

RAF

Insulation

Is the main insulated?

steam-rookie

wide open 1/2" pipe

Yes it is. All the way around. Only the tee`s and couplings  are exposed. 

jpf321

with 1" thick insulation?

is your insulation the recommended 1" thick?



keep in mind that the steam may be moving 25mph, but collapsing quickly as well to bring pipes up to steam temp. if you have wet steam rather than dry steam, that will cause more problems still. and also remember that steam must meandor around and check out all the possible nooks and crannies for other paths of least resistance before getting to the end of your main .. i know that in 1 book Dan said that the 'steam was moving faster than we could walk' .. but that's only like 7 or 8 mph .. and I'm not sure if that is really ever possible.



does anyone out there have very very speedy steam travel times, I'd be interested .. mine gets to end of well vented 65ft @ 2" main from a minimum 170degF boiler on average in about 10mins .. see data below



my pipes are somewhat (about 55ft) insulated with 1/2" insulation (my mistake)

steam-rookie

wide open 1/2" pipe

I have turns and nooks and crannies. I have 7 radiators, some with very long risers that tee off that main. You average is 10 min. for 65 feet.

I got 18 min. for  100 feet.

I want to speed it up

What can I do?

jim_72

slow steam

Why we don't know but more info would help. Below is the pic of your boiler you posted on your first thread.It apprears that your mains are insulated that good. From the photo it appears you have a single main that loops your basement and returns to your boiler on the right of the photo.Photo's of  all the piping near and around the rear of the boiler who be helpful. Question #1 do you have a equilizer piped off your single supply pipe that feeds your main. Question #2 is the return that drops back to the boiler below your vent (right side of photo) the only  vertical return in your entire 100' loopQuestion #3 is the entire main pitched down and away from the boiler?

steam-rookie

wide open 1/2" pipe

Those are all the pipes that are near and around the rear of my boiler.



Question #1 do you have a equalizer piped of your single supply pipe that feeds your main.  

Nope. That's it. that's the main. I will post some more pictures, but all you will see is that pipe on the left continue around the whole basement.

Question #2 is the return that drops back to the boiler below your vent (right side of photo) the only  vertical return in your entire 100' loop

Yes it is. That's it. Nothing else

Question #3 is the entire main pitched down from the boiler?

Yes. Very good pitch. piped and pitched to perfection by a dead man(respectfully) 65 years ago. never been touched, never been altered in any way

jpf321

you will notice...

if you look hard enough at my data above .. you will notice the fastest times are when the last burner cycle was recent .. and the longest times are when the last burner cycle was older .. my 15min time, the boiler sat dormant from 5hrs .. my 5 & 6 min times is when the boiler ran about 1hr ago .. this shows thatt it's all a function of how cool your pipes get during burner downtimes .. i bet if I had the proper 1" insulation, my average time would come down since my pipes might not cool as much between runs.



so the short answer, don't let your pipes cool, run for 10-15mins every 90mins whether you need to or not .. I now understand why a Heat-Timer device with a sensor at end of main or furthest rad may be useful.  .. there are 16 cycles of 90mins in a day. if you include the 10 mins of runtime .. you are running 14.4 cycles of 100mins .. that's 144min/day .. that's 2hr 24min .. that doesn't sound too bad to keep your system hot...of course, it would be better if you had an end of main sensor that told things to run for 10mins everytime the sensor hit a certain low-temp point. and if your system is kept hot, then your time to rads is significantly decreased .. 5or6mins to end of main vs. 10,11,15mins.

jpf321

i guess another question for you...

what is your typical dormancy between runs? as that's what seems most to matter. 

gerry gill

could you do a little test for us?

please flood the boiler and tell us if any water appears on the floor..or drips on the burners..just curious..just wanting to eliminate something.

jim_72

wet steam

What is happening is with no header to allow water to drop from the steam and no equalizer to return that moisture to the boiler as steam exits your boiler it is carrying water with it vertically to your main. With only one return at the end of the loop this water and any other condensation that drops out of your steam on it's 100' journey is being pushed along creating, for lack of a better word, drag on your steams progress.All things being considered- the age of your boiler and the piping - 18 minutes to fill with wide open venting is your real world. If and when you decide to make the plunge $$ for a more efficient boiler and piping you have what  you have and it's not the worst of all worlds.

steam-rookie

wide open 1/2

"i guess another question for you...

what is your typical dormancy between runs? as that's what seems most to matter".

 

Its not that cold right now in New York. I would say its about 2 hours sometimes of dormancy.



"could you do a little test for us?

please flood the boiler and tell us if any water appears on the floor..or drips on the burners..just curious..just wanting to eliminate something"

.

I would love to perform this test for you. thank you very much for your interest in this slow moving steam problem. How does one flood the boiler? How would I know if it is dripping on the burners? Where are the burners? If I flood the boiler wont the water go upstairs to the rads? Thanks in advance, The Rookie

Jeremy_16

Open Pipe Test

I ran the open pipe test on my system the other day. The longest main has 11 ft. of 4 inch pipe followed by 70 ft or so of 3 inch pipe. I had a ball valve installed on a 3/4 inch pipe where my main vent is usually located (I removed it for the test). When I opened the valve it took about 11 to 12 minutes for steam to arrive at the end of the main. That main is not insulated in all locations because some areas are inside walls. I thought it would have been faster as well...



I will be insulating as much as I can soon. That should improve the speed right? Is there anything else that can be done to improve the speed?

Mark N

Long Main

A 100ft main is a very long one to serve just 7 rads.  One continous main around the perimeter of the basement was how they did it in the coal heat days.  After the shift to oil and gas they started using 2 or more shorter mains.  I know 2 people that have now have 2 mains 1 parallel flow and one counter-flow.  I wonder if these were originally one long perimeter main and then somewhere along the line it was altered to what they have now to speed up steam delivery.  My house has 2 mains of the same length.  They are both 25ft.  I get steam to they end of both in about 3.5min.  Only about 30 seconds slower that an open pipe.  You ask about steam moving at 25 mph.  That only happens after the air has been removed from the pipes.  To flood the boiler all you have to do is turn on the water and raise the level up into the riser.  If water starts leaking onto the floor you have a hole in your boiler. 



Mark

steam-rookie

flood test

gerry gill January 22, 2010 @ 10:45 PM

Contact this user could you do a little test for us?please flood the boiler and tell us if any water appears on the floor..or drips on the burners..just curious..just wanting to eliminate something.



 I would like to try this test. I will need more info before I start.

How will I know if I have added/flooded with enough water?

Do I do this with the boiler on?

How would I know if the water is dripping on the burners?

Do I keep the fire box open and look inside there for water?

I need a step by step,  for me to try this test.

steam-rookie

Its getting better

This time I tried the open pipe test with the main still a little warm, as opposed to the last few times where the main was cold to the touch.

The steam ran around the main much faster

from start to open pipe-----7 min.    Wow!!  what a difference.

I think when the system lays dormant for to long the main cools off way to much

It seems like jpf321 is right.  Cold main----slow steam

steam-rookie

flood test

Taking into consideration the last test with the 7 min. result,

Does any one think I still need to perform the flood test?

Nick_C

Try this...

Turn on your boiler and put your hand on the part of the horizontal main closest to the boiler.  Wait until steam hits that point (you will know when this happens...it will go from cold/warm to very hot in a second).  It won't burn you, but you'll know when steam hits that point.  Now immediately start timing and go to the open port at the end of the main.  When steam hits the port, stop timing.  That's the vent time of your main.  My guess is that you will see it is about 3-4 min, which is fine.  Just sounds like your boiler takes a bit of time to start the steam process.  You could have an undersized (or underfired) burner relative to your boiler.  Also check that your boiler is not overfilled with water.  You may want to zee how fast the boiler makes steam (from a cold start) with relatively low water vs relatively high water.

steam-rookie

Nick-c

Thats exactly what I  have been doing. 

Best result so far is 7 min.

Nick_C

OK

ok...then i think you have an issue...have you turned off every radiator so that your open port is the only exit?  If so, and it takes 7 minutes to reach the open port with warm/hot pipes, then your boiler is either way undersized or isn't producing the rated amount of steam.

jpf321

1/2 vents exactly what you have

according to Mr. Gill's Balancing Steam Systems (available at this site) reference data, open 1/2" pipe will vent just about exactly the amount you are venting. You may get a little boost in speed if you move to a 3/4" outlet. Basically, for a 1oz/si 1min CFM vent requirement, you are at the limit with a 1/2 outlet. 

Mark N

How Long

How long was your boiler off when you had the 7min result? Was it 1 hour, 2 hours or only a few minutes. Under normal conditions how long is your boiler off in between calls for heat? If it is like 2 hrs that is how long you should wait in between tests. The hotter the boiler and pipes are the less time it will take steam to make it to the end of the main. Your losing less BTU's to the pipes. Also an open pipe is not how you would run you system. It will just let you know the best that is possible. Than you might want to invest in enough venting capacity to mimic the open pipe. In the resource section under library and old steam systems there is an article "It's all in the venting". Read it, it discusses the type of main that you have and how problems with were solved.



Mark

steam-rookie

jpf321

I think the 7 min. is pretty good.

I could easily change to a 3/4 open pipe because the tap size is 3/4.

The reason that I reduced to a 1/2" pipe is because the gorton #2`s that I have ordered come with a 1/2" thread. Why? nobody knows.

I asked this question a while back.  I asked why the smaller #1 has a 3/4 thread as compared to the way larger #2 with a 1/2" thread  . I was told it is a mystery.

jim_72

vents

As discussed in your prior threads your main contains approx 2.2 cu/ft of air . Two large Gordons  are rated to vent that amount of air. Use 3/4" pipe with 3/4x1/2x3/4" tees to make up your antler with a tee at the end encase you need to add . Good Luck

steam-rookie

Thanks jim

That's what I plan to do. I am still waiting for the two #2 gorton`s to be delivered.

I will maintain the 3/4 pipe right up to the new vents, then reduce.

Timco

return

Is there any swing check on the return stopping the return from pressurizing? If all the steam / pressure heads out the main, it will pressurize much faster than if the main & return has to pressurize at the same time. What is stopping the returns from seeing steam / pressure with no equalizer / check? Maybe isolate the return for a minute and see how fast the main heats?



Tim

steam-rookie

Timco

Wow!!  I don't understand any of that. Can you please explain?

I don't know what a swing check is but I`m pretty sure I ain't got one

Ain't got no equalizer either.

All I have is a single 2" pipe that comes out of the top of the boiler, travels 100 feet around the basement, and then turns straight down and into the bottom of the boiler.

Currently, with the open pipe test, I am averaging 7 1/2 to 8 1/2 minutes for the steam to make the 100 foot journey.

Thank you for your reply. I am looking forward to hearing from you again

Unknown

Swing Check

A swing check valve is a one way valve. I've attached a picture of one.

If you have one, it will probably be on your wet return line in the general vicinity of the boiler. Look for a fitting that looks like a tee with cap. Generally there will be an arrow on the side of the fitting showing direction of the flow.

- Rod

Timco

steam

High pressure seeks low pressure, and the check valve ensures all the steam goes out the main and cannot push water back into the wet returns. You should also clock your meter and ensure your firing rate is correct and was not lowered...if this was a vapor system, it would not make steam very fast by design. I service a couple vapor setups that are piped like yours with no equalizer or header.  The check may be a non-issue in your case but just a thought.



Tim

steam-rookie

Timco and rod

I took a look just to be sure. There is no swing check valve.

I do not know how to clock my meter.

I thought that I had a dry return? what makes it a wet return?

Just to be clear, This is one continuous 2" pipe. It comes out of the boiler, runs around the basement, and then just goes back into the boiler.

I am once again looking forward to your replies.  The Rookie

Unknown

Wet Return/ DryReturn /Clocking

The Dry Return /Wet Return concept can be a bit confusing at first  as it quite often is the same pipe.   Basically the return pipe starts out being called "The Dry Return" but when it drops below the level of the boiler waterline it is now known as  "The Wet Return" even though it maybe the same pipe!

When the boiler is not operating, the water in the Wet Return will be the same height as the water level in the boiler.  When operating, the water in the Wet Return rises (above the non-operating waterline) 1.75 inches for every ounce of steam pressure unless there has been a swing valve installed. Generally you don't want to have a swing valve in gravity wet return.



Clocking your meter- The idea here is to time your gas meter with only your boiler's burner operating and then calculate how much gas is being used in an hour. You then compare that to the figure on the data plate on your boiler If the comparison is way off you need to have you burner/meter checked by a pro. Here is a site that tells you how to clock your meter and has the conversion tables. Take several timings/readings and then average them out.

- Rod

http://www.bacharach-training.com/referpage/clocking_gas_meter.htm

steam-rookie

clocking the meter

Thanks for the great info. I did not know that clock the meter meant gas meter , I have oil. I understand what you mean about the under-firing. Is there a way to check for that with oil?

Rod, do you think the 7 min. is to long?

Do you Think that I should perform the flood test as Mr Gill suggested?

If so, How do you do a flood test, and what will it tell us?

Unknown

Boiler Test

An oil burner's efficiency has to be checked by a burner pro who has the instruments to perform this test.  Burners are an area best left to a pro who has the experience and the proper test equipment.



I think 7 minutes is quite reasonable. You might to insulate your fittings as this would probably help things a bit. Use this link and scroll down to a post I did titled "Insulation".

There is a source and instructions in the post where to find insulation for fittings (elbows tees etc,)

http://www.heatinghelp.com/forum-thread/129519/Getting-steam-to-the-mains



Boiler Flooding Test-  Boilers can develop corrosion at and above the waterline and this is a test to determine if your boiler has holes in it. Long times to make steam and lack of steam pressure could  be a symptom of a leaky boiler which is why Gerry Gill suggested you do this test. However since then we have learned more about your system so I think doing a test flooding is probably no longer necessary.



How to do a "flood test" - You do this test with the boiler COLD! The idea is to fill the boiler completely full of water and see if it leaks. It will either leak on to the floor or into the firebox. If it does, you then look closer and find what is causing the leak.

You flood the boiler by adding makeup water until the boiler is completely full. The big danger here is that theoretically if you aren't careful, you could over fill the system (pipes and radiators) and flood the house so you have to be very conscious of how much water you are adding. ]

If the safety valve is on top of the boiler you can remove this and visibly see when the boiler is full of water. If this method isn't possible, then make a mark on the glass sight tube one inch above the boiler's normal water level mark and then calculate the distance from that mark to the top of the boiler. Starting with the water at the normal water level, turn on the make up water and time how long it takes to get to the 1 inch mark and use that timing to estimate how long it will take to reach top of the boiler.

After a suitable period if a leak isn't indicated then you just drain the excess water back to the normal water level.

Be sure to then turn on the burner and bring the water to a boil for a few minutes as this drives off the dissolved oxygen in the "new water" which is the biggest cause of boiler corrosion. Because of this you should always bring the water to a boil whenever you add any water to the boiler.

I think at this point I don't think the indications are that you need to do a flood test though you may want  to do one somewhere down the line (spring or next fall) just to test the integrity of your boiler.

- Rod