And the pendulum has swung

Charlie from wmass

Lately I have been coming across many undersized steam boilers. Is anyone else seeing this trend?

The Steam Whisperer (Formerly Boilerpro)

Not in Chicago.....

Every Weil Mclain LBG I run into I pull the high fire wire(s)  and the system works much better, with the exception of some older models that run at 50% fire on low.  On the Peerless 211's, I run the regulator as low as possible and always improve things.   My running assumption that every steam boiler I see is at least 80% over sized (beyond the 33% Pick up factor) has not failed me yet. 

Charlie from wmass

I have had three out of four

last week that were less then the E.D.R. by 25% and no pick up factor was added to my E.D.R. numbers.

jumper

insoluble ?

Heat losses are less now with better windows, so what to do ?

Charlie from wmass

"Lucky" for the owners

the boilers are leaking. The buildings are not any better of envelopes then when they were built. I would say they are in worse shape as far as leakage.

The Steam Whisperer (Formerly Boilerpro)

The big question is...

did they heat evenly anyway or can they be made to heat evenly?

Charlie from wmass

If they heated evenly I would not have been there

we are talking EG 65 boilers where even me being conservative I would install an EG 85

JStar

Size

I used to work for a company that did all of the mechanical work for an energy audit company. For steam replacements, they only wanted a house heat loss. Of course the new boiler was going to be too small. New insulation, new windows...

ChrisJ

small?

When we moved into this house in April of 2011 the boiler that was installed was a Burnham V83 rated for 283sqft.  The EG-45 I installed rated for 392sqft barely gets by.



I can only assume the V83 was installed because the house is 1700sqft and the guys that installed it shouldn't have been working on a steam system.

nicholas bonham-carter

A trend

Could they have been installed by the same people in that time?

How were the homeowners able to bear the cold?--NBC

Mark N

Getting By

Chris what do you mean by barely getting by? You've posted in another thread also recently. If that is the correct size boiler is should be more than adequate.

ChrisJ

barely getting by

Mark,

When I first fired the system up with the new boiler my mains were not insulated for the most part.  At that time I had two radiators that refused to heat no matter what I did.  Within a few days I insulated most of the mains and finally those two radiators would heat.



With insulated mains and proper venting the system works great, in my opinion a perfect match.  Though it takes forever to build 0.5PSI even during a recovery, makes me wonder sometimes.  I wonder if the boiler was a little bigger if I would have had those issues with the Hoffman 1As also, any little droplet of water in the valve orifice was enough to stop a radiator from heating, permanently.



Perhaps the way I worded it was wrong, or misleading but the point was the EG-45 is in no way oversized so the V83 that was there with practically no insulation on any steam piping could have never worked right.



Sorry for the confusion.

Mark N

Got it

Now I understand. Have you ever read Boilerpro's article on boiler sizing? That V83 might have been able to get the job done using his methods.

ChrisJ

boilerpro

I don't think I've read his article, but I do recall discussing the problem with him here.  Early on I didn't realize the boiler was rotted so I wanted to try and get things working best I could.  I believe venting the radiators really slow was the secret.

The Steam Whisperer (Formerly Boilerpro)

Well....

if they meet heat loss and are two pipe with insulated mains, supply orifices should do the trick with some generous main venting and minimal return line venting.  One pipe gets more challenging....if they have the typical radiator covers at least that drops the radiation capacity by25%.  Big main vents and little adjustable radiator vents is the best.   Also, when getting into multiunits, I find alot of radiators off, so that can help.

Your'e probably on target re: energy auditors......no training in steam.

Mark N

Boilerpro Article

Here is the link:



www.heatinghelp.com/article/323/Boilers/1551/Taking-Another-Look-at-Steam-Boiler-Sizing-Methods-by-Dave-Boilerpro-Bunnell

Charlie from wmass

SIngle pipe systems

They are apartment buildings so the tenants that were cold removed their vents completely. No insulation and no venting.

The Steam Whisperer (Formerly Boilerpro)

Bad situation......

seen it before.  I had one like that and I found that a huge plate on the bottom of theold snowman boiler had fallen off.  Combution test showed about 52 % efficiency. Took a block and held the plate in place, sealed up a bunch of other leaks and got the efficiency up to 76%.  Now that the heat was going into the system we had to put the vents back on because steam was getting though to the end radiators.  At least most of the mains were insulated. 

Your boiler didn't have a chance with all that against it!

will smith_4

combustion

What kind of burner did you have on that one? Atmospheric, I'm guessing?

will smith_4

heat loss calcs-

Don't matter when it comes to steam. You have to match the boiler with the connected load.  Steam doesn't care what kind of windows you put in. A lot of folks that learn about heat calc don't have any clue as to this very key point about steam-because not enough trade schools have anyone teaching load calc that know anything about steam.