Need help identifying old spencer boiler

Widword

I'm trying to decipher all the information on the data plate of this Spencer Boiler. I can make out some numbers, but I have no idea what they mean or what they represent/stand for.

I know this is a gas steam boiler; the building it lives in was built around 1933/1934, and it's still fully operating. Any help would be appreciated. Thanks!

mattmia2

That is a converted coal boiler. How it is fired now was set up by whoever did the conversion, there is little info on the ratings plate relevant to how it is operating now. What are you trying to figure out?

EdTheHeaterMan

the only rating that might match is on page 218 of this Beacon Boiler Guide, near the bottom. there is a 2G26 hand fired boiler Spencer Type "A"

The Steel Boiler Institute (SBI) rated this boiler at 186 Sq Ft of heating surface. I believe that was the rating at the time it was build that is most like the Sq Ft of steam on todays boilers. All the other Spencer boilers that may have been hand fired do not have any ratings that come close to this boiler's identification plate.

I do see a 26 stamped on that place but the pre-printed 2G is not visible on that plate any more if it was ever there. This is my best guess and based on the burner that is there now, that burner has the proper capacity for that boiler's firebox.

You can double check this info by measuring the firebox dimensions 30" x 54" and see how close they match. What do you need this information for? If you want to size a replacement boiler you never use the size of a boiler that ols to select the replacement boiler. That is how you end up with oversized boilers. read this story: https://www.heatinghelp.com/systems-help-center/how-that-steam-boiler-got-to-be-so-big/ . If this is a steam boiler, you want to measure the connected radiation. If this is a hot water radiator boiler then you need to do a load calculation using Manual J or Hydronics institute form 1540-WH if this is a large residential building, or perhaps the ASHRAE Heating & Cooling Load Calculations since this is probably a commercial building

I just looked at your original Post…. you said it is a steam boiler. Measure the connected radiation Equivalent Direct Radiation (EDR). there are some generic charts for that. If you have some really different radiators then you may need to purchase Dan's book https://www.heatinghelp.com/store/detail/e-d-r-ratings-for-every-darn-radiator-and-convector-youll-probably-ever-see/ and look up your different radiators to get the number you need to select your new boiler. When you get that number don't do any more math to convert from EDR to BTU or anything else. Just take the total radiator EDR that you added up and match that number to the Sq Ft steam on the new boiler's rating specification.

EDIT:

For example if your building' radiators add up to 2000 Sq Ft EDR or less then select the model number Crown 24-05 from this specification chart. Since that 1983 Sq Ft Steam rating is the closest number to your actual EDR. there are lots of room added for what is called piping and pickup built into those ratings. so you can choose one that is a llttle smaller. (NOT A LOT SMALLER).

You may find that you only have 1590 Sq Ft of EDR since some old radiators were replaced and things have moved around a little since 1934. Then you may select the 24-04 in that case.

By no means DO NOT USE THE OLD BOILER as a guide for a replacement boiler. If your installing contractor is considering that as the proper way to select a replacement boiler, then you need a different contractor.