Steam in a hot water boiler??????

David Sutton_2

ok ..... got a burham V 76-t fired at 150 x 80b this is what it calls for.has a 2" surply two taco 1612c3n1 5.75 circs, 1 1/2" return, no coil, has a 8148 control and next to it a new gauge both the gauge and the control read 140 degrees unit go off on temp, and steam is comming out the air vent in the back top section of the boiler

we drained down the boiler removed the coil plate and all the return piping and made sure the boiler was not plugged up in the bottom water tube, reconected the return pipe to the boiler and with the coil plate off we filled the boiler and watched the water rise up in all the sections evenly. replaced the coil plate and refilled the boiler and ran it up and wala... steam!!!. now when we shut down one of the circs the steam stops...., The rep from burnham said that the circs should have nothing to do with it and that the should still be circulating thru the hole boiler . i dont belive the system was designed to run with both circs running at the same time. but if they dont they do not get heat to the 2nd floor hydro coil.anyone got any ideas...been in contact with burnham on this and the frist rep said this could not be happening and i am waiting for a call from Glen S

thank you for what ever help you can offer or if you see something i may have forgot to look into...David Sutton

[Deleted User]

How many GPM are you moving through the boiler?

What is the Delta T through the boiler while this is happening? Can you tell if the water is moving so fast that there is a pressure drop through the boiler?

Noel

David Sutton_2

how would you go aout it???

the presure on the boiler is reading at 12 lbs while its running. would i need to install a gauge in both the surply and the return ??. at 2" pipe at30'of head =50 gpm for each circ

[Deleted User]

That's an AWFUL lot of water flowing through the boiler.

I think I'd run the water to the system around the boiler, and flow the water through the boiler slower, like in a primary/secondary piping arrangement. I'm looking to see what Glenn says....

Noel

David Sutton_2

boiler up date....

returned to the boiler, checked the presure, the presure was still 12 on the gauge , talk to the chool superintendent, he said he was running both the circs because the unit on the top floor rear was not heating and had air in it, i told him we will install air venting at the unit and brought the presure up in the boiler to 18lbs, and shut down the second circulator, told him systenm was not designed to run them both. we did not install the system , but we can fix it. as of now the temp in the boiler is even, and the steam has stopped.

i belive that noel is right, that the water is moving to fast thru the boiler the presure is greater in the front sections than the rear and that the water is not circing thru the hole boiler and the fire is heating up the still waterin the last section to the point its making steam,..... now the world is a peace. thank you for your help David

David Sutton_2

have not yet heard from glen

Jacob Myron_7

Steam In Boiler

I think the tip off was when you raised the pressure to 18 PSI. You stated that the steam stopped when you increased the pressure...

To find the operating pressure in a water heating system you must measure the height of the piping system.

Measure from the highest point in the system (air handler and coils) to the lowest point in the system (probably the bottom of the boiler.

Assume the the static head is 30 feet. Multiply 30 times .434. A system pressure of 13 PSIG will allow water to reach the highest point of the system. Add 2 PSIG of pressure to assure that air will not turn to steam in the piping.

Factored in to that equation is the differential pressure that the pump creates. If the pumps cause a differential pressure of more than two PSI the pressure at the coils will drop back to 13 PSI. At that juncture steam may form in the coil area and be pulled to the boiler with the returning water.

Due the fact that both pumps seem to needed to heat the entire building the differential pressure can exceed the differential pressure of one pump and walla steam forms.

This is born out by the fact that when one pump ran the steaming condition stopped.

In some systems you may need to increase the static pressure as much as 5 PSIG.

The pumps in the system may be sized wrong. Normally one pump should do the trick, the second pump is there as a spare in the event pump # 1 fails.

You solved your own problem by increasing the static pressure.


Jake

Mark A. Custis

Jake:

I love you guys that do math. I sell and blue sky, and I hope it helps others here and there. The numbers needed to be in this business are astounding. I get lost with three years of college math yet the soon to be archeteture student does stuff in her head the takes me days. I will help sell something you need to sell in return for knowing you are there

Thanks for what you have taught me today.

Mark

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David Sutton

Thank you Jacob....

i do thank you for your help, and i wrote that down...David Sutton

Steamhead

Boiler Over-Pumped

This sounds like something I ran into a while ago with a 1925-vintage Spencer. The water moved so fast thru that boiler that it couldn't pick up much heat, and pockets of steam were forming inside as a result. Go to

http://www.heatinghelp.com/newsletter.cfm?Id=119

to read about it.

The Taco 1612 will pump up to 70 gallons per minute at low head pressures (see chart). Two of these pumps will move 140 GPM. The Burnham V-76 was rated 192,000 BTUH net output. 140 GPM will move roughly 1,344,000 BTUH!

You are WAY over-pumped here. The water is spending so little time in the boiler that it can't pick up any heat. The boiler rating of 192,000 BTUH would require 20 GPM. A Taco 110 or 0010 or a B&G 100 are three examples of a pump that will deliver this amount of flow (depending on head pressure).

How much heat does each coil require? You can determine the water flow each coil needs from this figure. And I'd also consider installing a separate circ for each coil- Pumping Away, of course. This will let you size the circ to the flow and head requirements of each, and let you work on one while the other is still running.

Let us know how you do!


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Unknown

David

I have been in NYC and Western CT for the past few days and have been somewhat out of cell phone range. I did call the 413 area code number that tech services gave me this afternoon while on the way back from New Milford,CT and got no answer. They had told me just to contact a gentleman named David with no last name or complete explanation. Sure wish they had given me a last name.

It certainly appears as though you have way too much pump for too little boiler. I can't ever recall seeing a pump that big used with a residential boiler. Way too much GPM and head capabilities. I would suggest checking what the load for that boiler actually is and the distance of developed pipe to and from the boiler and then having a pump sized for that. Sounds as if they had a spare 1600 series pump on the shelf for one of the larger horse power boilers that may be in one of the other schools. I will be around on Monday David and can be reached via e-mail at gstanton@burnham.com . Hope this helps.

Glenn

David Sutton

thanks steamhead...i just..

got that chart this afternoon the system was not designed to run them both, i shut down the 2nd pump and running just the one and so far all is well ,thank you David

David Sutton

thank you Glen my phone was..

in the truck ( dumb luck huh) and when i called you back i got your voice mail and the phone whent dead lol. i will e-mail you whats up thanks ..David