Load Calc Complete

Hollyfeld · Post by **Hollyfeld** » Tue. May. 27, 2008 7:11 pm

I performed a load calculation on my home today and came up with about 60,000 Btuh. My current oil fired boiler is rated to 114,000 Btuh. The upstairs living space in my house is roughly 1000 sqft. and the finished basement is about another 700.

The 60,000 Btuh was a result of putting very detailed information about my house - Roof construction, wall construction, exposures, windows, outside temps, and desired inside temps. The outside temp I used was 0. Here in New Jersey that does happen, but not very often, and the last time it did was a few years ago and only for a couple days.

Do I need to size a boiler the same size as my current oil fired one?

I'm really liking the Harman VF3000 and there is a dealer only 20 minutes away.

I also started liking the EFM's, mainly the refurbished ones, and one of these would certainly satisfy the load.

Would one of these boilers burn more coal to satisfy the same load?

Post by **Rob R.** » Tue. May. 27, 2008 9:01 pm

The Harman VF3000 should work excellent, as would an EFM 520. The EFM 520 would have extra heating capacity, and the difference in coal usage between the two would probably be negligible.

LsFarm · Post by **LsFarm** » Tue. May. 27, 2008 9:06 pm

Both of those boilers should burn very near the same amount of coal to generate the same BTU's. I doubt that there would be more than 5% difference in efficiency between the two. That's a rough estimate,, but both burn their coal very well, the only difference may be how easy the inside of the boilers are to keep clean. The accumulation of flyash on the inside boiler surfaces insulates the water jacket from the heat of the coal fire.

Greg L

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Yanche · Post by **Yanche** » Tue. May. 27, 2008 11:05 pm

What load calculator did you use?

Sting · Post by **Sting** » Tue. May. 27, 2008 11:16 pm

Hollyfeld wrote:Do I need to size a boiler the same size as my current oil fired one?

Not if you keep the current oil fired boiler as a back up! Undersize the coal boiler and it will operate at full capacity for longer portions of the season. It runs better trying harder!

Then in those two or four days that the heat calc sizes for worst case - let the oil boiler fire ocasionally to help pick up the load. Its good for the oil boiler to work once in a while anyway.

Hollyfeld · Post by **Hollyfeld** » Wed. May. 28, 2008 8:15 am

Yanche wrote:What load calculator did you use?

I used Carrier's Hourly Analysis Program V4.20