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Specifications of mid-efficiency fuel oil furnace ResStock v2.2.4

asked 2021-01-12 20:34:01 -0600

sashadf1 gravatar image

updated 2021-01-13 08:52:35 -0600

Hi all,

Curious what fuel oil distillation number (no. 1 or no. 2) is assumed when I specify an 83% AFUE or 80% AFUE (mid-efficiency) fuel oil furnace for CR03 (Maine) in ResStock v2.2.4.

I am assuming it is no. 2, since this is more common in residential space conditioning.

I am using the lower heating value aka net caloric heating value for no. 2 fuel oil in my analysis since a mid-efficiency furnace is non-condensing. To represent this, I my heating value is 99% of the minimum of the range for fuel oil no. 2, which yields a value of 135,630 BTU/gallon.

Unsure if this is the correct LHV for fuel oil no. 2, confirmation would be nice.

Per engineering toolbox, No. 1 fuel oil is used in vaporizing pot-type fuel oil burners and No. 2 fuel oil is used in rotary and atomizing gun-type fuel oil burners.

What burner is assumed? Since vaporizing pot-type fuel oil burners are rare in colder climates and do not use No. 2 fuel oil, for CR03 I am assuming it is either rotary or atomizing gun-type.

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answered 2021-01-13 12:43:55 -0600

139000 Btu/gal (I believe it is no. 2). This can be seen in unit conversions here:

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This is using the HHV; however, if you are specifying a mid-efficiency non-condensing furnace shouldn't the LHV be used? The above value of 139000 Btu/gal is too high to be the LHV for no. 2 fuel oil. I am trying to convert mbtu burned to cost. For propane analysis, specifying an 80% AFUE furnace, I used the published propane LHV of 84,250 Btu/gallon in converting mbtu burned to $. Is this a mistake?

sashadf1 gravatar image sashadf1  ( 2021-01-13 15:46:06 -0600 )edit

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Asked: 2021-01-12 20:34:01 -0600

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