US DOE on Balancing and Tuning Single PIpe Steam

Boiler Talk

Steam System Balancing and Tuning for Multifamily

Residential Buildings in Chicagoland - August 2012



<a href="http://www.nrel.gov/docs/fy12osti/55483.pdf">http://www.nrel.gov/docs/fy12osti/55483.pdf</a>



This is an interesting document from our government. 

Gordo

Thanks for Posting This

It's nice to see steam not automatically being bashed.

The Steam Whisperer (Formerly Boilerpro)

My experience in Chicago

I just gave the report a quick reading and there are a number of things which are not in step with my observations in Chicago

1) It states only 1 in 10 boilers had incorrect near boiler piping. I have found that about 95% are piped incorrectly

2) No statement is made regarding how oversized the boilers are.  The Least oversized are usually right on.  The typical installation, however, is about 80% oversized based on radiation.

3) It appears they did very little work with main vent balancing.  This is reflected in the huge temperature differences between the hottest and coldest units.   10F difference is unacceptable.

4) The systems are supposed to be balanced before cycle controls are added (according to the control manufacturers).....this was not the case.

5)  They recommend the use of Gorton radiator vents.   These vents on the largest settings will overwhelm the main vents, causing system imbalance.

Gordo

2" Pipe and Fittings

Ah, yes.  It seems threaded pipe and fittings only go up to 2" ;-).  In our area, most installers that attempt to put in residential steam boilers simply don't use any size larger.



The larger mechanical contractors construct welded boiler-breaking crowbars and call them "headers".



At least this Pamphlet does not  ascribe to the "rip-it-out-and-put-in-scorched-hot-error" mentality.  It's a start.

Steamhead

Still

they need to read Gerry and Steve's venting e-book, apply that to their projects and log the results.

The Steam Whisperer (Formerly Boilerpro)

Bashing

I believe it quoted " these systems were built for longivity, not efficiency".  or something to that effect.    There still seems to be the idea that steam is inherently inefficient.   I do agree however, that it is a start.  However, I've found that just completing main vent balancing alone and retuning the boiler to the proper firing rate will save about the same amount as thier study.  I am glad they concluded that the three main improvements need to be studied separately.  As an FYI....probably most or all the boilers in the installations they worked with were grossly oversized gas atmospherics.....the norm here in Chicago.    I found an ocassional power burner in those sized buildings, but they are rare.

jumper

greening steam

Holohan's book briefly discusses enclosures. Why can't there be enclosures with dampers or shutters to regulate output ?