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0 Answers

Adding minisplits to second floor of Cape Cod Style

I recently had a HVAC contractor come out and give me some options on my cape cod style house in suburban Philadelphia (Zone 4A). Currently there are no return ducts from the second floor and minimal supply ducts as well, leading to a noticeable temperature difference on the second floor. The house layout does not allow new duct work to be run to the second floor easily, so it would be expensive and probably still undersized.

Asked By Andrew Sirianni | Oct 20 17
19 Answers

Are my minisplits modulating or short cycling?

Hello- first of all this site has been an incredible resource. I did most of my own research in adding 4 mini splits to my 1940's home. It was primarily for AC and heat for the shoulder seasons as we really enjoy our 1 pipe steam heat (although older boiler). I went with 2x Fujitsu (not XLTH) condensers with 2 heads each. A 12k per floor (open kitchen area, top of stairs, attic playroom), and 7k in the master.

Home has been retrofitted with new windows, open cell in the rafters, blown-in in the walls, definitely on the tighter side for it's age.

Asked By Kjmass1 | Oct 4 17
5 Answers

Mini-split for Phoenix, AZ Duplex?

Hello everybody,

I'm Ben and I'm new to GBA. Well, I've been reading lots of articles here and searching the Q&A, but this is my first post.

I recently purchased a duplex in downtown Phoenix, Arizona. It needs pretty much a total rehab. Most of the flooring needs to be replaced due to water and/or termite damage. This gives me the opportunity to seal the crawlspace if I want. Luckily, the exterior walls are all concrete block, so no terminte damage there.

Asked By Ben | Oct 7 17
12 Answers

2,700 sq/ft house climate zone 6 R20-R27-R40-R70 7,300 HDD -1 Design temp...minisplit sizing and zones?

First of all thank you all of have contributed to this website. I've researched a lot and it's provided valuable insight. I'm designing my house right now. 2x6 framing with zip sheathing as the primary air barrier and 4" exterior polyiso R42. Basement walls will be 2" polyiso with 3.5" roxul R27 (should I increase this?. Slab 4" XPS R20, and attic R70-blown in with poly as the air barrier. The plans show sliding windows and sliding doors but everything will be single doors and awning/casement/fixed.

Asked By user-6925805 | Sep 27 17
6 Answers

Ducted heat-pump water heater

CZ 3A - Greenville, SC - mixed humid

I have been reviewing some studies online regarding ducting a heat pump water heater and think it might make sense in my new house. Here are the results from the study above, which assumes a garage located heat pump WH in central Florida:

Cooling Season Savings
Indoor to Indoor 3.8%
Outdoor to Indoor --1.2%

Heating Season Savings
Indoor to Indoor -5.9%
Outdoor to Indoor -17.5%

Asked By Norman Bunn | Oct 13 17
3 Answers

I've heard that some heat recovery ventilators produce ozone. Is that true, and if so how?

How can you know you are buying one that doesn't?

Asked By mark romwalter | Oct 8 17
25 Answers

Another garage heating question


So I'm building my dream shop/garage, then I going to build my house.. So my wife is making sure I stay on budget.

Building is 64'x 40' x 14'

ICF frost walls that will be 4' below grade and 2' above grade then 12' of 2x6 walls on top for 14' ceiling.
Walls will be taped and sealed OSB best I can and have 3" (reused) Polyiso on exterior and filled with Roxul.
Attic spaced will have blown in cellulose, R???
Floor will have 4" foam under slab. If needed??

South facing side (64') will have 4 large 5' x 5' windows, casement style on half of 2 windows.

Asked By Dave B | Oct 4 17
3 Answers

HVAC setup in small basement

Hey folks,

Asked By Jamie Royal | Oct 5 17
4 Answers

Fresh air for mini-splits

My HVAC contractor is planning to use Mitsubishi mini-splits, some ducted, some not. I am on board with this idea, but we are looking at fresh air alternatives. I was originally looking at the AirCycle g2, but it seems that the Mitsubishi wiring may be a problem, since it is not "standard". Also, it seems the Mitsubishi fan runs continuously, albeit at a low level. Other than an ERV, which may be a more costly alternative in my climate zone, what are my alternatives for getting fresh air into the home?

Asked By Norman Bunn | Oct 3 17
53 Answers

Zone 6b, Mass. Coast, mini split / Fujitsu?? Mitsubishi?? size?

I live in a coastal town north of Boston. My 1200 square foot house (600 upstairs, and 600 downstairs) is heated via electric baseboard heating. I never go above 60 degrees in the winter and still spend over $400 per month and this is with each room with its own thermostat and me turning them all down to mid-50's when no one is around and only turning up those rooms where we are. It is ridiculously cold in my house in the winter.

Asked By indoorsy | Sep 5 17
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