Replies

1. Expert Member
   Dana Dorsett | Jan 08, 2019 11:58am | #1

   A two zone multisplit would be super-overkill and wouldn't modulate, running at lower-than advertised efficiecy.

   This is almost certianly within the capacity of a single half-ton Mitsubishi FH06NA or 3/4 ton FH09NA, either of which modulates down to about 1600 BTU/h. But a 3/4 ton mini-duct cassette type would be easier to split the output between two spaces. The Fujitsu -9RLFCD would be a decent choice, with more flexible installation options and higher efficiency than the comptition, modulating down to about 3000 BTU/hr. Alternatively, a pair of separate 3/4 ton LG "Art Cool" mini-splits that can modulate down to ~1000BTU/hr out would still modulate at high efficiency most of the time.

   Of those options I'd lean toward a mini-ducted solution, unless for fire or privacy reasons there can't be any air communication between the two sides.

2. 
   geli | Jan 08, 2019 08:24pm | #2

   Dana, thank you very much for your reply. I’m not sure that a shared mini-duct unit will work well for us with a wood shop on one side and drawing studio on the other. Would you lean towards the Half ton Mitsubishi FH06NA or one of the 3/4 ton units that you mentioned, if we are to go with two units?
   Thanks again for your time.
   Much appreciated,
   Geli

3. 
   joshdurston | Jan 08, 2019 10:35pm | #3

   With a wood shop, I would consider using some sort of ducted unit that has enough static pressure to handle appropriate filtration. You want the filtration to be up to task and easily maintainable.

4. 
   Jon_R | Jan 08, 2019 11:38pm | #4

   The ARU9RLF used in the Fujitsu 9RLFCD has a fan that only modulates over a 1.33:1 range. A poor choice for humidity control at loads below ~9K Btu/hr.

5. Expert Member
   Dana Dorsett | Jan 09, 2019 11:45am | #5

   A pair of LG LA090HSV5 3/4 ton "Art Cool" is probably the right solution run completely separately. They can modulate down more than 30% lower than the Mitsubishi FH06 or -09. (1023 BTU/hr vs. 1600 BTU/hr). The SEER & HSPF numbers are lower, but would provide better shoulder seaons comfort due to the lower modulation capability and the miniscule loads they are serving. (The COP at min-modulation at +47F isn't great, but when the load is only 1023 BTU/hr it's a "who cares" sort of thing.) They're a few hundred cheaper (each) than the Mitsubishis too.

   https://www.ecomfort.com/manuals/lg-f8c00e52278ebc4728b6f7afe8a9c914.pdf

6. 
   geli | Jan 09, 2019 08:24pm | #6

   Hi All, Thanks for your input. I’ll need to work out the filtration issue in the wood shop. I do run an air scrubber when I’m using machines. I also do a good amount of green woodworking and bench work with hand tools. I think we’ll go with Dana’s suggestion of the LG LA090HSV5 3/4 ton "Art Cool" units.
   Best,
   Geli

7. 
   davidsmartin | Jan 12, 2019 02:17pm | #7

   Dana -- If the poster were in Vermont instead of South Carolina, what would be your advice? Looking at NEEP's listing of cold weather heat pumps I see several that can modulate to much lower levels than was possible a couple years ago.

1. Expert Member
   Dana Dorsett | Jan 14, 2019 10:28pm | #9

   In VT I'd be looking at a pair of half ton Mitsubishi -FH06NA, unless a formal load calculation showed it really needed to be a pair of -FH09NAs (not likely, even at -13F if the windows are closed. :-) )

8. 
   geli | Jan 14, 2019 08:59pm | #8

   Dana et all,
   Ordered The LG - LS090HSV5 which has the same outdoor compressor unit as the LA090HSV5 that Dana recommended but with a std. white indoor unit - for those of us who still see the 1970’s when faced with the Smokey Mirror finish on the LA indoor unit.
   Thanks again.
   Geli