Deciding on a basement mini-split
Hi –
I am deciding between the LG Art Cool Gallery 9000K BTU LA090HVP or their 12000 BTU LA120HVP for our basement, mostly because we like the picture option, trust the brand, and have been told by various HVAC folks that 9 or 12K will suffice, but honestly have discounted all those that have said my basement requires 18-24K min. Doubt that, because:
The living space of the basement that I predominantly wish to heat is approx. 32′ x 27′, or say 900 sq. ft.
Currently unfinished, but 6′ of the below grade walls will have 2″ of R5 rigid foam, so total R10, and rim joists (approx. 2′ of above ground) will be 3.5″ of closed cell spray foam, so basement will lean towards well insulated.
Basement averages mid to high 50’s now, and would like to get it to 68/70.
I’m in Northern NJ where my Heating 99% Dry Bulb is 10 degrees, so DeltaT is 60 we can assume.
Any help appreciated and thanks in advance.
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Replies
I think 9,000 BTU/h is probably plenty. But here at GBA, we discourage guessing. We encourage anyone designing a heating system or cooling system to start with Step One: a heating load and cooling load calculation.
More info in these articles:
Saving Energy With Manual J and Manual D
How to Perform a Heat-Loss Calculation — Part 1
How to Perform a Heat-Loss Calculation — Part 2
Calculating Cooling Loads
-- Martin Holladay
I know I shouldn't use a contractor that doesn't do one, but they are either all over the map or want to charge a few hundred just for that, being there's minimal margin in doing so, and eats into their labor charge (they make no money on the units really). So I have a hard time getting an HVAC contractor to do a Manual J or load calc just to get a quote. They want assurance I'm going to use them, but that depends on their quote!
Just get a cheap $25 resistive heater and use that to find the BTU you need. You people are making things needlessly hard and expensive....
And you probably don't even need a mini split... Btw, have you checkout mini split cleaning, mold gunk yet?