My Winter Coal Burning Formula for 2014 (Blaschak)

Post by **Rob R.** » Fri. Dec. 13, 2013 3:49 pm

kstills wrote:
I guess the issue I have is when I run the heat loss calculator, admittedly a very imprecise tool, I have to input a very high level of insulation in order to reach 27k per hour heat loss at 20f. I just don't my house has that much going for insulation wise, but then again I've only been charting coal use accurately for 2 days now, so maybe it all makes more sense after a month of doing this.

A few months ago I posted somewhere about the futility of sizing a boiler for an old house based on a heat-loss calculation full of estimates about insulation and infiltration. A heat loss is part of the process, but it doesn't get the last word.

kstills · Post by **kstills** » Fri. Dec. 13, 2013 4:01 pm

Rob R. wrote:
kstills wrote:
I guess the issue I have is when I run the heat loss calculator, admittedly a very imprecise tool, I have to input a very high level of insulation in order to reach 27k per hour heat loss at 20f. I just don't my house has that much going for insulation wise, but then again I've only been charting coal use accurately for 2 days now, so maybe it all makes more sense after a month of doing this.
A few months ago I posted somewhere about the futility of sizing a boiler for an old house based on a heat-loss calculation full of estimates about insulation and infiltration. A heat loss is part of the process, but it doesn't get the last word.

I took a very scientific approach towards my boiler installation.

Month 1 buy boiler.
Month 2-5 Ignore boiler completely (it was summer)
Month 6 Hurry up to install boiler (it was cold out)
Months 7-48 Learn about all the things I did wrong in months 1-6.

I actually replaced one boiler with another of the same general size. I now realize that the original boiler had been installed prior to the house being insulated and the storm windows going on, so the real boiler size should have been some fraction of what I actually bought.

As for heat loss, I only did that after the installation, and until I figured out how to accurately track the coal usage, it was merely a guess.

Now I will know exactly what my heat loss is, based on the coal usage. Well, close enough to lie about it, anyway.

So far, it looks like it's much lower than I would have anticipated, but I still have lots of data to collect.

kstills · Post by **kstills** » Mon. Dec. 16, 2013 12:33 pm

lsayre wrote:It turns out that my initial formula for this heating season gave to much credit to my Blaschak coal. My revised formula for this heating season is:

Coal burned for the day = HDD's x 1.55 + 4 lbs.

Where:
HDD's = Heating Degree Days (base 65) = 65 minus the days mean temperature
And 4 lbs. = coal used for the homes average daily DHW needs instead of home heating

This formula is matching my consumption data just about perfectly to date for October and November (the only heating data I have so far this season), and it shows that Blaschak is delivering roughly 15% less usable BTU's than did last seasons UAE Harmony.

Larry,

What have your HDD's been for December so far?

lsayre · Post by **lsayre** » Mon. Dec. 16, 2013 12:43 pm

kstills wrote:
Larry,

What have your HDD's been for December so far?

548.5 HDD's through yesterday.

I've subsequently revised my formula to read:
Coal burned per day = Daily HDD's x 1.43 + 4 lbs.

kstills · Post by **kstills** » Mon. Dec. 16, 2013 2:37 pm

lsayre wrote:
kstills wrote:
Larry,

What have your HDD's been for December so far?
548.5 HDD's through yesterday.

I've subsequently revised my formula to read:
Coal burned per day = Daily HDD's x 1.43 + 4 lbs.

470.5 here, with a caculated 1.39 +10.5.

Means I run out of coal March 28 at 6:03 pm.

lsayre · Post by **lsayre** » Mon. Dec. 16, 2013 2:39 pm

kstills wrote:470.5 here, with a caculated 1.39 +10.5.

Means I run out of coal March 28 at 6:03 pm.

Sounds like great planning. You will run out just in time for spring.

Our usage per HDD is pretty similar overall.