BTU ratings for radiators

GP

Hello to Don and others. (Don, thanks for returning my call.) Let me update you and the others what I need desperate help on: I'm the maintenance person for an old church bld. built in 1931 here in Chicago. It's time to replace the beast that's been heating the building since ??? I believe the one (a Kewanee) we have is original. It went from Coal to Oil to its current configuration of Natural Gas.

We've had two bids that we are reviewing. 1. Contractor A checked the meter reading and boiler plate (on the power flame) and clocked it at 3 mill BTU (which matches the plate which is 2.8 mil I beilve. 2. This second contractor (we'll call him "B") went around looked at the radiators, counted some of the sections and said, 1.5 mil is sufficient.

With such a discrepency, I now think I should do my own research and see how many BTU's our radiator system will really need. So, that is where I am now. I have the measurements from all the radiators on the property. I figure I should calculate the load the radiator system needs, then we match a boiler to the radiator system (Don, I was pleased to find out that 2 of your articles support this. Titled "how to replace an old steam..." and "Replacing your old steam boiler.")

The vast majority are National Radiators. Some of the sections are 9 inches deep by 22, 24, 33, 35 high (all sitting on the floor). Some are 7 inches deep by 26 inches high (all of thise are wall mounted type).

We have 8 finned radiators with blowers. For each radiator, there are 2 sets of fins. Each fin is 5 by 5 by 45 inches. These are in the main sanctuary with produce a lot of heat (the ones who's blowers work).

I'm not sure who manufactured these finned ones, but I found 2 odd balls type that looks like a car radiators nearby that measures 13 x 39 x 2.5 with a sticker of Bodine Wisconsin. My guess is these had blowers at one point, but the blowers are not there.

Can any one help me with calculating the BTU's of what I have? I'm not sure if it's appropriate (sorry if I'm breaking protocol), but I'm willing to pay a consulting fee if you can help me rather quickly. I can supply any data you need with pictures.

If there's a simple formula for the National radiators, I could calculate this on my own if you think it's worth it. The formula I found elswhere on the web is:

(width x height x 2.5 / 144) x 240 = SF x BTU rating

Is this formula bogus? Don, you said the 2.5 rating could be off for my radiators.

I appricate any feedback. I'm also very open for more bids if you are in the Chicagoland area. Now, I'd like bids on steel boiler since someone knowlegeble told me cast iron will only last 20 years at best.

THanks in advance,
Gene Pierson
Covenant Presbyterian Church of Chicago.

Alan R. Mercurio

Gene

Check out this link here at HeatingHelp.com I think it's just what you're looking for?

http://www.heatinghelp.com/shopcart/product.cfm?category=2-59



Your friend in the industry,

Alan R. Mercurio

Oil Tech Talk

DanHolohan

some info

Here's the EDR rating per section for the Nationals with the six tubes, based on the height of the radiator

22" high = 3 sq. ft. EDR per section

23" high = 3.5 sq. ft. EDR per section

26" high = 4 sq. ft. EDR per section

32" high = 5 sq. ft. EDR per section

38" high = 6 sq. ft. EDR per section

One sq. ft. EDR is equal to 240 Btuh when we're working with steam.

The blower units look like Nesbitt. Measure the front of the cabinet and let me know what it is in inches.

The other, narrower National has how many tubes?