Sizing new boiler

bhinkle50

First I wanted to say thank you for all the info you guys put out here. I've been lurking this forum for about a year learning as much as I can for what I hoped would be a boiler replacement this spring. Well, as they say "best laid plans". I don't think we're going to make it as the old boiler has started to leak and it seems to be getting worse.



In reading this forum and a couple of Dan's books, I've learned that I have about 7 different problems that I plan to correct as a part of this replacement. The first step I am doing is measuring out the size of my boiler as I think it was oversized to what I need.



I have a total of 16 radiators. 14 of them are American Radiators "Murray" fin style. I found an article on this site that shows the EDR for the various sizes (enclosure and radiator combined). The remaining 2 I have I can't find using the search. They are Trane fin style.



I've attached a picture here is someone could help with the EDR info for these it would be great.



They are 54" long and the enclosure itself is only 13" tall.

bhinkle50

Currrent info

The current boiler I have is WM EG75 that has a gross BTU rating of 300k and a net I=B=R rating of 180 MBH.



So far, my EDR calculation is about 350 without these 2 radiators, so unless I'm doing something wrong it appears the current boiler is overrated by a decent margin.



The Murray sizing I used was from this link:



http://www.heatinghelp.com/files/articles/1273/55.pdf

ALIGA

U can probably get a eg45 or eg 50

Or a Williamson. Which is a rebadged weil

kcopp

what is the depth .....

of the convector?

Steamhead

Maybe one of these?

http://www.heatinghelp.com/files/articles/1280/218.pdf



As our host would say, it pays to wander off the Wall.

bhinkle50

Looks about right, but convector depth seems different

The convector is 5 3/8" wide. I couldn't tell some of the dimensions in the pdf on that link, but it looked like the one that was closest was 6 1/16".



These are also in a cabinet that is only 13" high, so I'll probably have to work up a custom number.



Using the table in the doc for the enclosed 6 1/6 at 55", the 18" yields a 31.



Do you think it's reasonable to estimate these radiators at 25 since the cabinets are only 13" and this convector isn't quite as wide?



Thanks again for all the help.

Steamhead

In another reference

the Hydronic Rating Handbook, a flat-top, 6" deep, 14" tall, 56" long Trane wall-hung convector has a rating of 46.5 square feet EDR. I could not find anything else that was close to your units, so this is the rating I would use.