EDR Calculation Help - In Need of a New Boiler

ncilexie · February 1

Howdy folks!

I want to preface this by saying I recently purchased and moved in to my grandparents home; one that was not well kept in terms of maintenance of the natural gas boiler, pipes, or radiators (or anything really) so I'm picking up the pieces so to speak.
I'm currently having an issue where my boiler is running my well dry, and the automatic fill is running half a dozen times a day or more. I have a heating technician coming to look at the system on Monday, however from reading Dan's book I think there's a crack or hole in the boiler (if I'm lucky it's a clogged return). It's a Burnham PIN4-SNC manufactured and installed in 2003. I have no clue if the technician who installed this boiler did the math to size the boiler correctly or not, but here's the current boiler's information:

I'm looking at my options for replacements, and know that I need to calculate the EDR for each radiator, and I know the technician that is coming to look at the problem won't know how to properly size the unit (no technicians around me that are super well versed in steam that I can find). I have a total of 7 radiators across 2 floors in an 1100 sqft home near Binghamton, NY. As far as I can tell there are no missing radiators.

I'm having a hard time calculating the EDR as these radiators aren't matching up with the square footage of the charts I'm seeing. This house is a hodge podge of different radiators.

I have four radiators that look like this. I can't make out the manufacturer, but it looks like it starts with a T or an I:

They're all 19" tall and have 16, 18, 18, and 28 sections respectively.

I have one radiator that is a four column radiator. Again, no manufacturer information that I can read, but maybe a triangle logo with three letters:

This one is 19" tall and has 16 sections

Upstairs I have these two units:

First has 20 sections at 19" tall

Second has 14 sections and is 29" tall

Any and all help is super appreciated. I'm hoping to get this figured out or have a ballpark number before the tech shows up on Monday afternoon so I make sure I'm buying the appropriate replacement.

Thank you!

Jamie Hall · February 2

Someone will point you the book "Every Darn Radiator" — or just make a VERY educated estimate. Don't get too hung up on exact numbers, though — if you get within 10 percent you're fine.

If you are adding water as frequently as you seem to be, you do have a leak somewhere. It could very well be in the boiler, and that is not hard to diagnose. It could also, however, be in any of the piping which is below the waterline of the boiler in the basement, and that you may be able to see (are there any buried pipes? Those are almost automatically suspect!).

ncilexie · February 2

All pipes are above ground thankfully, and it seems like everything below the water line is right next to the boiler and easily accessible. The return is harder to visualize as it runs within a crawlspace that has random garbage in it, but I don't see any wet dirt in the basement or any puddles next to the boiler. I'm not super thrilled to crawl around the crawlspace but it seems okay:

It looks like 5 of the radiators are Thatcher, one is Burnham, and the final one is still a mystery. I'll give the mystery a guesstimate and see what I come up with.

mattmia2 · February 2

Where does this pipe go?

ncilexie · February 2

Apparently a spigot?

EdTheHeaterMan · February 2

Lots of folks read the chart incorrectly. until you have experience looking at lots of different homes you may select the wrong radiator from the chart. Your radiators all look like Tube type (Not thin tube, Not column)

This chart is from Weil McLain boiler sizing guide on page 10. The instructions on how to measure the radiator correctly start on page 9. W on the chart stands for width of a section. Not width of the whole radiator. So the Depth of the radiator would be a better description of that measurement. Once you know the EDR of one section then you count the sections and multiply the EDR per section by the number of sections in that particular radiator. Here is a illustration of your radiators to be clear.

So, if, for example, the brown radiator has 4 tubes and is about 7" deep (W) and about 20" tall (H) from the floor to the top of the cast iron (including the legs) then, that radiator has about 2.25 EDR per section. if that radiator has 15 sections then that radiator has a total EDR of 33.75 SqFt . If it has 16 sections then it has a total EDR of 36 Sq Ft. (it is difficult to see the last few sections) Just match up the radiators in the chart to the radiators you have (as close as you can get) and start doing the grade school math to get your system's connected EDR.

The next mistake folks make is converting EDR to BTU to select the proper boiler. DON'T DO THAT! Use the total connected radiator EDR and match it to the Net Steam EDR of that boiler.

The I=B=R ratings of years gone by are now called AHRI NET ratings. that is because someone decided that we don't need 3 or 4 different rating agencies. So Institution for Boiler Research changed their name to Hydronics Institute. Hydronics Institute merged with Gas Appliance Manufactures Association (GAMA) another rating agency. Eventually GAMA became part of the Air-Conditioning, Heating, and Refrigeration Institute (AHRI). those folks rate the air conditioners efficiency and performance. So, before there were the folks that rated Boilers that connect to radiators, and the Folks that rated gas appliances like furnaces that connect to ductwork (and sometimes oil fired appliances but not always) and the folks that rated air conditioners that sometimes get connected to furnaces (but not always). Now somebody decided that we didn't need all these different agencies to do all that testing on all thise different heaters and air conditioners and heat pumps. And all tha t test equipment was getting old and needed to be replaced and all those old buildings were getting … Well… OLD. and so they all got together and put some old farts out of a job in order to save $$$$ .

I could ramble on and on about ratings and agencies and the fact that they were telling us how efficient our appliances are in possibly the most inefficient way, but there is not point in doing that.

EBEBRATT-Ed · February 2

My first question is how did it heat with the boiler you have??

The reason I ask is your old boiler is rated at 271 sq feet of steam

I calculated your radiation at 425 square feet. I could be off a little but not that much.

ncilexie · February 2

Going off the sizes of the radiators, it actually looks like most of them (Thatchers) are thin tube. The only one that's throwing me is the Burnham (white 5 column) as it doesn't quite match up with any of the sizes. I did a best guesstimate and used the EDR for a thin tube 5 column, since it looks like the EDR is the same for both a 17 and a 23 (I'm assuming it's the same for everything in between):

It looks like my current boiler is slightly under, but I'll call that a win. I thought it'd be way off!
Thank you for the guide, I appreciate it immensely!

EdTheHeaterMan · February 2

https://forum.heatinghelp.com/discussion/comment/1839642#Comment_1839642

Where did you get the measurements from? Just looking at the photos? Can you be sure the hight is correct? and do all the Thatcher radiators have the same amount of sections?

ncilexie · February 2

@EBEBRATT-Ed honestly it's hit and miss. My bedroom would only get to 62 degrees (F) when the thermostat was set to 68 until I replaced the vent on the side of the radiator. I'm going to guess that they're all old as ****. Living room with the largest radiator is always toasty, and unfortunately that's where my thermostat is (albeit on the other side of the room).
Second level is cold but I'd say that's because there's no radiator in the hallway; only in the two rooms upstairs have radiators.

This house was built in 1928, so it's also lacking in insulation…

EdTheHeaterMan · February 2

@ncilexie it sounds like you have. better handle on EDR than most folks. Since you can measure and determine that the Thatchers are thin tube, you calc is more better.

random12345 · February 2

The 4 greens look like they say Thatcher. That's the Thatcher Furnace Co. Couldn't find any trade catalogs online. My guess is the center-to-center distance of each section is 1.75". That accurate? If so, refer to this:

https://babel.hathitrust.org/cgi/pt?id=mdp.39015035429805&view=2up&seq=1697&size=175&q1=r174-40

They accepted the 1943 practice recommendations but not 1947 curiously. 2.3/section for the 6 tubes, and should be 1.6, not 1.67 for the 4 tubes.

The first white one is a Burnham slenderized, but I think your measurement is off. Must be 20" tall. Check if distance between sections is 1.5" or 1.75":

https://s3-us-west-2.amazonaws.com/catsy.782/Baseboard+and+Radiators+Product+Data+Sheet.pdf

Should be 1.8/section not 2.

Second white one is another Thatcher I think, but this one the height must be 32" right? Should be 3.7/section not 5. The width of a section is 1.75" right?

The other is accurate I think. Where does it say "R&R"? Any writing around either the top or bottom hex nuts on either side?

I'm getting 280.6.

Steamhead · February 2

Check the section spacing (center of one section to center of the next one) on your radiators. That brown one is probably a regular "Tube Type" with a section spacing of 2-1/2" , whereas the others are either 1-1/2" or 1-3/4" which would make them "Thin Tube". Then use the proper EDR for each type.

ncilexie · February 2

Correct, the Thatcher radiators have a section spacing of 1.75", but the one upstairs is indeed 31" instead of 32" (measured from the floor to the top of the radiator). The Burnham is 20" tall with a 1.5" section spacing, and the old brown tube type has a section spacing of 2.5". Here's a picture of the logo:

Redid my calculations for the updated EDRs on the Burnham and the taller Thatcher and am at 280.1. A lot closer than the first time around :)

mattmia2 · February 2

The number on the boiler has a 30% pickup factor subtracted from for the rest of the system losses it so the output is actually 30% more than what the ratings plate says. The load from the piping is likely far less than 30% so a somewhat smaller ratings plate number will likely work fine.

Steamhead · February 2

https://forum.heatinghelp.com/discussion/comment/1839721#Comment_1839721

But, if the boiler comes with a CycleGard low-water cutoff, the burners shut off periodically for level checks, so the boiler won't be actually making steam for periods of time when the thermostat is still calling for heat. ISTR @The Steam Whisperer documented this but can't find it quickly. So I wouldn't try to use a smaller boiler.

Sure, you could replace the CycleGard with something else, but that would probably void the warranty.

random12345 · February 2

It's highly likely that the brown rad is 2.25/section, but I haven't seen that logo before. If you're interested in identifying the manufacturer, post some more pics. I would look for writing or other symbols on each of the end sections in the following areas: most commonly in the area you already photographed, but it could also be on the bottom hex caps or on one of the tubes. The Thatcher upstairs may be 31" if the legs are a little shorter. Is the leg height 2.5" from the floor to the center of the bottom hex cap? The reason I ask at this point is purely because I enjoy the challenge of identifying radiators. No idea why. 😁

Steamhead · February 2

https://forum.heatinghelp.com/discussion/comment/1839820#Comment_1839820

By the time that type of radiator came out, ratings were pretty much standardized. So the chart posted above should be fine.

random12345 · February 3

https://forum.heatinghelp.com/discussion/comment/1839821#Comment_1839821

Agreed. It's academic for me at this point. Kind of like Antiques Roadshow.

ncilexie · February 3

You all are awesome, I appreciate the assistance and the enthusiasm!
Here's some additional pictures of the brown radiator @random12345 I took a wire brush to the logo to try to get a better idea of what it says but I'm still not sure what it says/is. No additional writing on it that I can see (bottom hex caps look the same, and nothing on the tubes), though it looks like it's been painted a few times.

Looks like the legs are a little shorter on the tall Thatcher:

Technicians came out to assess the boiler today. We accidentally flooded it last night (turned the boiler's breaker back on after working on some joists/wiring in the basement) and we had water pouring out from the inside of the boiler onto the burner. Along with that information and watching all the steam coming out of my chimney on a 40 degree NY day, they're stating there's a crack in the inside of the cast iron. No visible water from any pipes. Should be receiving a quote for a like model Weil-McLain or a Peerless. Fingers crossed it's not too bad but they're thinking around $6k. The joys of homeownership 😅

bburd · February 3

Your existing near-boiler piping is incorrect; there is no header and the equalizer comes off the bottom of the takeoff to the system. If you've read Dan's books you already know this, but it's important that your new boiler be piped per the minimum recommendations in the boiler manual for size, configuration and material (black steel for steam carrying pipes; copper is acceptable below the water line).

Otherwise this is an opportunity to correct faults in the existing system like water hammer, poor balance or slow heating. How well did it perform before it began to leak?

random12345 · February 3

Thanks for those. Richardson & Boynton. Never had heard of them before:

https://oiltechtalk.com/wp-content/uploads/2018/12/richardson_-boilers.pdf

https://archive.org/details/TheRichardsonManual/page/n251/mode/2up Can't find a picture of the rad you have, but it won't change your EDR calc either.

I feel for you on the boiler room flooding. Same thing happened to us. The technician came over and filled the boiler up into the risers, panicked when all that water came out. All he had to do is turn off the water supply… 🙃

No quotes allowed on the site FYI. At least you know for sure there's a crack in the boiler and it needs replacing. Now comes the hard part…choosing a decent installer. Maybe someone on here can give you a recommendation or would be willing to come up from NYC.

ncilexie · February 4

The previous piping pictures were just the return lines. Copper piping is from the automatic feeder. There is a header, although I'm measuring an inch or two shy of the minimum 24" from the header to the water line of the boiler. Not too sure why they installed the main steam line right off the equalizer, but I planned on having whoever is replacing the boiler use the specs from the manufacturer/installation manual. Reuse what you can but certainly replace and reconfigure what needs to be reworked.

The system heats fine and evenly, but she certainly has her fair share of water hammers and pings. I know some of it is definitely missing insulation (working on that as well). No clue on how well it performed before the leak; I just moved in mid-November and have had high heating bills and constantly running water from the start. My grandmother who lived here for 50+ years thinks everything that had happened was normal (all the noises, the steam coming out of the radiators, and the water level not being consistent) so no luck on what "normal" is.

If anyone knows of reputable contractors who know their stuff about steam around Binghamton, NY, I'm certainly looking and open to referrals! The guys that looked at the boiler today want to reuse what's there already (which is a no no) so I'm looking at options.

Everyone on the contractor listing in NY is either in NYC or Long Island, so I'm not too sure about willingness to travel.

Steamhead · February 4

@Mad Dog_2 ?

dabrakeman · February 4

If you are in the 280sqft edr range I would say use a Burnham STMX100 or WM EG35. Both rated at 258sqft. Leaves you 22.5% for pickup which should be plenty even if you are off slightly on radiator measures.

Get the contractor to acknowledge in writing that he will "maintain or exceed manufacturers minimum recommended piping sizes per the manual and follow piping configuration guidelines per the manual."

ncilexie · February 19

The saga is complete!

Had a company come out who knew their stuff and geeked out a bit when I mentioned Dan's book. They measured the radiators and got 279 sqft so we were on the money. Installed a Utica boiler to manufacturer's specs. Took them all day, but I think it was time (and money) well spent:

Thanks again to everyone who helped identify and measure out my radiators for a new boiler. I really appreciate it! Fingers crossed for a smaller heating bill and a happier well!

RTW · February 20

Quote post above:

"you calc is more better"

Here we go again …. just right click for proper grammar

Regards,

RTW

random12345 · February 20

Congratulations. Let us know how everything goes. They told you how to skim right? You'll need to do that to get all the oils off the surface. It's normal for it to smell out your radiator vents for a while.

ncilexie · February 20

They did not, but they're coming back out today to skim it as the water is still surging upon my request. They'd originally added 8 way treatment (I have mixed feelings about this but they'd already done it by the time I got downstairs. Plus the pipes and radiators could probably use a good cleaning). I'll make sure to watch the process in case I need to skim down the road. I know there are a few recommended how to guides online for skimming, so if I forget a step then I have something to fall back on.

ethicalpaul · February 20

8-way is great, but not until the water is clean. Then it will help it stay clean.

ncilexie · February 20

@ethicalpaul I figured that would be the case. I see many skims in my future; I don't think the old boiler water was ever treated. Also given the amount of sediment and pipe boogers (rust/iron deposits) that ended up in the water from the well running dry over the past month I'm sure some made their way up into the boiler pipes 😅 oh well! It'll be worth it in the end.

The Steam Whisperer · February 20

I believe that is a rebadged Dunkirk model. The factory skimming instructions are incorrect unless they have changed the casting design recently. The side tapping in the boiler is lower than the intermediate tappings, so if you skim directly from the 2 1/2 inch tee on the side of the boiler, only the end section gets skimmed. The water in the other sections is too low to make it over to the side tapping. A 2 1/2 x 1 1/2 inch bushing in the side of the tee should bring the water level high enough in the boiler to properly skim the intermediate sections.

ethicalpaul · February 20

You're right @The Steam Whisperer I thought for sure they did have a bushing in their manual, but they don't. And the Utica and Dunkirk manuals are nearly identical (they might be the same company, or they are sharing manuals!)

Is the side bushing actually lower than the interior ones? That is a very odd choice on their part. @EBEBRATT-Ed or @JUGHNE gave me this same advice in 2018 and I've never forgotten it.

You shouldn't have to do too many skims on that small boiler, @ncilexie . It should give you a very nice long life if you be sure to minimize replacement water (and mine still lasted like 25 years even though the former owner was careless—I took it out of service before it rusted out so it might have had more years left).

When I busted it apart with a sledge hammer I was very impressed with the castings (at least to my amateur eye they were very beefy and the steel push nipples were perfect looking).

EDR Calculation Help - In Need of a New Boiler

Comments

Categories