Coal Gun BTUH ratings

Patrick,

How are the ratings for the coal gun boiler defined. A S-130 boiler is rated at 130,000 buth. Is this gross output including jacket losses? Or net output to water?

I don't know how a manufacture tests the boiler but the A-A Antratube BTU rating was determined in the Bureau of Mines report by running it full tilt and measuring the BTU's transfered to the water. It came up a little short of 130,000 BTU. The AHS S130 would be similar.

You can determine the BTU's delivered by any boiler if you know the supply and return temperatures and the water flow rate. One way to measure the flow rate is to know the pump head vs. flow rate curve. This is published by the pump manufacturer. Then you measure the pump inlet and outlet pressure. It's a simple calculation the convert this pressure difference to pump head. Then you just read the flow from the pump curve and calculate the delivered BTU.

You are correct Yanche. The 130 is gross, but many people claim to have tested it as very close.

The question is has AHS had their boiler tested using accurate test instruments or just relied on simple test proceedures. Does the factory feel confident on the ratings being gross output to the water. If a direct drive model is purchased there is no adjusting draft fan speed.

While you can adjust the fan speed on belt drives, and increase your output considerably, we as a company have not developed any firm numbers for that type of modification. Also, you may decrease the life of the fan.

The 130,000 is a gross number, and our overall efficiency is mid to low 80's.

Keep in mind we try to be realistic, conservative, and honest.

Any manufacturer can make any number happen in a lab.

Steamup, What you need to understand is with coal there is no standard for coal quality. Other fuels, home heating oil, natural gas, propane and electricity have known standards for the BTU content of the fuel. Therefore a standard test specification for BTU output vs. the fuel input can be created. These are the DOE or IBR ratings you see on boiler nameplates. This is not possible with coal, because the coal quality varies considerably. While it's a straight forward procedure to measure the BTU output of any boiler in the case of coal it's not all that useful. The boiler manufacturer could test with a very hot high BTU coal. Obviously the boiler would produce a corresponding large BTU output. For you if your coal is of poor (low BTU) quality, no matter what adjustments you make will produce the manufactures rated output.

While it is important to match the boiler size to your homes heat loss, there is a wide range of operating BTU output on any coal boiler. Also remember that building heat loss calculations are worst case calculations based on the coldest day of the year plus some margin. The design coldest day of the year is a possible but rare event. If the 130,000 BTU rating of the Coalgun is close to your heat load it will work. It just doesn't matter if it's a gross or net rating.

Yanche, no offense but I fully understand that there is no standard for rating coal boilers and coal quality varies. This is the reason for all of the questions. I=B=R ratings discount boiler DOE ratings by 15% to account for piping losses and pickup. Coal boilers are not rated by any specific standard and manufacturer's usually do not do extensive testing for ratings, so one must rely on manufacturer's recommendations.

My situation is kind of like buying a full size pickup. Do you get the 6 cylinder model for fuel economy or the 8 cylinder for heavy loads? At this time I have enough feel for the ratings to think about it and really need to figure out how much I need to heat the workshop to determine if the lower fuel efficiency of a larger boiler would be more economical than installing two boilers or supplementing with oil fuel.

Thanks for your input.

Does AHS have a website?? I tried researching the AH S130 boiler but all the searches keep coming back to the NEPA site. I tried searching Yanche Alternate Heating Systems also and that also just came back to NEPA

I don't think you need to know the exact precise output of the boiler as much as you need to know the exact heat loss of the structure to be heated.

thanks richard. Don't think they have their site maximized or whatever you do to have google "hit" on the search 'cause they didn't come up easily! (Wouldn't make me a happy camper if it were MY business!!)

If you are using the Google search in the upper right here that's a special Google search that only returns results for nepacrossroads.com

Standard Google search returns their site for "alternate heating systems". One trouble with their name for other results is that it's also going to be a common term many business will use.