I am looking to heat an 800 sq ft basement apartment here in Virginia. Well-insulated with only one 40' southern exposure wall exposed to the elements (the other walls are either below ground or shared with an unheated part of the basement).
I found that I could effectively heat the room to 70F with outside temps below 30F with 2 space heaters running at 1,250 and 1,400 watts, respectively. Assuming 100% efficiency on electrical space heaters, that is a combined 2,650 watts x 3.1412 BTU/watt = approx 8,300 BTU. I assume that my math is correct?
With electricity @ $.125/w here, I suspect that an direct-vented LP wall heater might be more cost-effective...but I am not positive. Just filled my LP tank @ $1.89/g.
Been talking to sales people from both Empire and Rinnai - they keep suggesting units in the 30k-35k BTU range...which makes no sense to me. Assuming 80% efficiency, they are talking 24k-28k of BTU output.
Yet, I did it with 8k BTU output albeit at a cost of 2,650 w x 24 /1000 = 63.6 kWh @ $.125 = $7.95/day. Too expensive.
My questions:
1. Is my 8k BTU calculation correct?
2. If yes, why do I seriously need a 30k BTU DV wall heater?
3. Any guesstimates on how much LP I would burn per day with a unit that size?
4. Any reasons to decide between Rinnai vs Empire?
Thank you in advance.
John (aka Snakebit12)
I found that I could effectively heat the room to 70F with outside temps below 30F with 2 space heaters running at 1,250 and 1,400 watts, respectively. Assuming 100% efficiency on electrical space heaters, that is a combined 2,650 watts x 3.1412 BTU/watt = approx 8,300 BTU. I assume that my math is correct?
With electricity @ $.125/w here, I suspect that an direct-vented LP wall heater might be more cost-effective...but I am not positive. Just filled my LP tank @ $1.89/g.
Been talking to sales people from both Empire and Rinnai - they keep suggesting units in the 30k-35k BTU range...which makes no sense to me. Assuming 80% efficiency, they are talking 24k-28k of BTU output.
Yet, I did it with 8k BTU output albeit at a cost of 2,650 w x 24 /1000 = 63.6 kWh @ $.125 = $7.95/day. Too expensive.
My questions:
1. Is my 8k BTU calculation correct?
2. If yes, why do I seriously need a 30k BTU DV wall heater?
3. Any guesstimates on how much LP I would burn per day with a unit that size?
4. Any reasons to decide between Rinnai vs Empire?
Thank you in advance.
John (aka Snakebit12)
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