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Re: Steam Boiler Sizing (Convector radiators)
This one is 60.3 of my measurements are correct.
There are adjustments based on the cabinet dimensions and the actual cast iron dimensions. This is the chart I am using and you can see if the cabinet size changes the amount of the heat output changes a little for the same size cast iron convector.
As you can see on your 68" long radiator, changing the cabinet hight by just 2" can change the EDR up to 4 Sq Ft. That is why I need you to doublecheck the measurements
Re: Steam Boiler Sizing (Convector radiators)
OK in the book that is a 20" radiator. 4" legs. 18 sections = 40.5 EDR
Re: Steam Boiler Sizing (Convector radiators)
Here is the first calculation. Based on these measurements the EDR for this convector is 28.9
If the measurements are different please correct me.
Re: Short cycling boiler. I'm stumped.
Put a ball valve with a tee that has a boiler drain on it between the valve and the tank. If the tank has pressure in it and you shut the valve off and unscrew the tank, that water under pressure will be spraying out everywhere. The boiler drain will allow you to drain the pressure from the tank while keeping the rest of the boiler under pressure.
Webstone makes fittings designed for this application. They are designed for expansion tanks and have the ball valve and drain together on one fitting.
Definitely something to consider once you get this other problem with the power venter taken care of.
Good job @EdTheHeaterMan for all the help he's provided.
Re: Musings on the "Design Day"
@DCContrarian is technically right about the percentile bit. And statistically it's actually even more complicated… I was just trying to get across a general feel for it.
One other minor item… in a sense that 95/99 stuff is a measure (not that good a one) of the variability of temperature — how often and how far it moves from the annual average. That variability actually seems to be increasing (and climate modelling shows it should) with the result that those design temperatures probably are too high (too warm). But that, folks, is a whole other can of worms!
And yes, @ethicalpaul , I have lived in places where the heating system couldn't hold the indoor temperature up. Of the houses I've lived in, I can think of three which couldn't.
Re: Musings on the "Design Day"
My current house. Built 1922. We renovated the 1st floor 20 years ago; the 2nd floor is original wood lath and plaster. Replaced a coal fired converted to oil 1.25GPH Nozzle Thatcher Gravity with a 100,000 BTU/h WM Boiler. Zoned 1st 2nd floors.
Eastern Isl of long design 5°F. When near that and the NE wind begins to blow the couch gets pulled away from the 2 in the wall radiators, the wood cover by the stair's radiator gets removed and the boiler runs probably 100%. When it's at 0°F or below we maintain 65 inside overnight. Once the sun comes up so does the house. Thats close enough for the 1 or 2 times we've lived here with those conditions.
I remember growing up Summer curtains came down and Winter curtains went up. I'm sure that would help here.
pecmsg
Re: Old high school 2 pipe steam boiler with trane fin blower units.
You have bad traps in the building . The steam is getting into the returns and the condensate pump and going out the vent pipe.
In addition to that your condensate temp is way too high……another indication of bad traps.
What steam pressure are you running? I would lower the pressure (just make sure you can get heat to all areas) until you get the traps fixed.
Re: Short cycling boiler. I'm stumped.
As long as it's the same ratings as the existing, it's fine.
Are you sure the pressure switch isn't just doing what a pressure switch does? The boiler passages are clear? Flue pipe joints are tight? Motor RPM correct (amps)? Fan is clean? No obstruction anywhere? You guys must be cold.
HVACNUT