Need some help understanding steam, pressure and widgets


Old 02-03-12, 07:39 AM
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Need some help understanding steam, pressure and widgets

Burnham V7 boiler, 3.75GPH, 3 stories, 8 risers and about 26 radiators in an apartment building. Two questions:

1) There are two return lines, one original and one added in the 50ís. The newer one heats up really fast and I thought changing the main vent on the slower line would make it heat faster. Especially since the valve on it was as old as you and I combined and the vertical stub itís attached to remained cold after the main return pipe was hot. So I installed a Gorton 1 and nothing changed. The horizontal steam pipe still gets hot on either side of the T which has the main vent attached. Then eventually the stub gets hot, possibly by convection. Is that normal operation? I thought the condensing steam would go up the vertical stub which leads to the Gorton before it continued back to the boiler.

2) I thought the pressuretrol wasnít working. The boiler never seems to cycle even during a long run. There are dual pressuretols on a 3/4" antler; a 404 and a manual lockout Honeywell. The 404 is set to 2PSI on the outside and 1.5 on the inside dial. The original pressure gauge is useless. I turned the manual lockout one from 6 PSI down to 4PSI to see what would happen, and it tripped mid cycle. Thinking thereís something amiss with the 404 and with an inquiring mind, I attached a new brass pigtail with a new gauge to end of the antler and it didnít read more than Ĺ PSI. The antler was unremarkably muddy, regardless we cleaned it out and the pigtail leading to the 404 is clear enough to blow through. Why wouldnít the gauge be reading higher or the 404 respond?
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Old 02-03-12, 03:56 PM
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The idea of the main line vents is to get them full of steam as quickly as possible... and from what I understand of your post, that is happening? You say the RISER isn't getting hot? That would be due to the vents on the rads I think, but I may not be 'getting' your description.

The OPERATING CONTROL, that is, the 404 should be allowing 2 PSI of steam to build. With a 1.5 DIFF setting, it would/should come back on at 0.5 PSI. The HIGH LIMIT control should cut the burner at it's setting...

I suppose it's possible that BOTH of those controls are whacked?

Can you show us some pics of the setup?
Old 02-03-12, 07:11 PM
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Sounds like you may not be getting steam to the end of the main. The heat could be coming from condensate. Do you hear the vent hissing? If so does the hissing stop? If the stub to the vent doe snot get hot there is no steam there. I believe the gage and operating 404 is accurate and the high limit 404 is defective.
Are the steam mains insulated?
Do all the rads heat. You don't need steam pressure to heat a steam system. My saying is "steam pressure is excess steam" There are many properly sized steam boiler operating with very little or no pressure. Steam moves fastest at "0" pressure. Steam will always go to the radiation as that is the low pressure point.
What is the sq ft of radiation in the building? What is the sq ft of radiation the boiler can produce, V7 what?

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