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Re: I Need Help Determining Coal Boiler Size

Posted: Fri. Jul. 25, 2008 7:12 am
by beatle78
jose,

I have a KA-4 that is new to me this year. The last 3 years I've had a coal stoker stove. Both systems have a hopper that I have to fill. If I could fit an auger feed system into my home I would!! That way I don't have to tend to the coal as much and I can focus on dumping the ashes every couple of days and that's it!

Re: I Need Help Determining Coal Boiler Size

Posted: Fri. Jul. 25, 2008 12:43 pm
by Yanche
mikeandgerry wrote:http://www.hvaccomputer.com/index.asp is an ASHRAE Manual J online calculator that is available for one month for $49 for homeowners. (Pros can buy it for unlimited use for $389 ) It does both the loss for heating and gain for cooling. I found it to be spot on, easy to use and very detailed. For example, if you have one wall that is half concrete, half of that insulated, half of that uninsulated and the rest of the wall framed and insulated, it allows you the flexibilty to breakdown that wall to calculate those value exactly. It was the best $50 I spent on my project. I would never have followed manual j exactly without it.
Be aware that the manual J analysis software sold by http://www.hvaccomputer.com/index.asp follows the ACCA, Air Conditioning Contractor Association, manual 7 procedure. It's been superseded by the ACCA manual 8 procedure which claims to give more accurate BTU load number especially for cooling loads, i.e. summertime heat gains. Both will give accurate and very similar results for heating, i.e. wintertime heat loss. I mention this because building code regulations almost always require the latest version of a procedure or specification to be used. So I you are doing an analysis for code approval ask what they will accept before you do anything, especially buy any software.

Mike is correct that a Manual J analysis is very useful and the software makes it easier to do the procedure correctly.

Re: I Need Help Determining Coal Boiler Size

Posted: Sat. Jul. 26, 2008 10:19 pm
by mikeandgerry
John,

Thanks for the info. I will keep that update in mind if I put in a central AC unit. The accuracy of the heat gain for my home is borne out in my experience by having to add window AC units in my house to cool it to the design temps. In years past prior to calculating the heat loss and gain, we ran a couple of window units and they cooled the house except on the hottest days, to 75degF. Certain rooms were much too warm, etc. This year, and last, I spent a few bucks on additional units. The known capacities of the units and the Man J requirements from my calculations are now in balance. I can now cool down to 74 (my interior design temp) in most rooms on the hottest days! In my case perfection is only impeded by the limitation of the window style AC unit and it's poor distribution system!

Anyway, for my purposes, I found hvaccalc very helpful. In our neck of the woods, man j is only required for new construction installations. Why, I don't know. Whosoever understands the local codes must be a god!

As always, I defer to your vast engineering experience and appreciate your input.