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14 Answers

Water cooled refrigerator coils

This may seem weird, but I’m curious...

We just bought acreage in west central Florida and we’re planning our home. We plan on making everything as energy efficient as we possibly can, and I ve been researching geothermal ground loop heat pumps.

As I’m grabbing some leftovers out of the fridge, I feel hot air being blown on my feet from the condenser coils underneath. At the same time I hear the AC kick on outside. The lightbulb flickers on above my head... I’m running the AC to cool the room that is being warmed by the fridge...

Asked By LT.Son | May 19 18
2 Answers

Ducted/concealed mini-split without supply or return plenums - straight out the wall?

I'm planning to install a "ducted"/concealed Daikin LV unit on the second story of my house. I haven't been able to find any definitive answers on plenum requirements, or lack there of.

the plan includes hanging the unit from unistrut in the hallway, observing all of the required tolerances for access and space around the unit. A sofit will then be built around the unit.

Asked By neockder | May 23 18
5 Answers

Fasteners for concrete, brick, and CMUs

For an upcoming article on fastening various materials to concrete walls, brick walls, and CMU walls, I'd like to hear about your favorite fasteners.

I'm looking at fastening three types of materials:
1. 1x4 furring strips directly to a concrete wall, brick wall, or CMU wall.
2. 2x4 furring strips directly to a concrete wall, brick wall, or CMU wall.
3. Continuous rigid foam (2 inches thick or more) directly to a concrete wall, brick wall, or CMU wall.

I will also look at a fourth situation:

Asked By Martin Holladay | May 23 18
10 Answers

Spray foam questions

Hello all, thanks for any help in advanced.

Asked By Stanger133 | May 20 18
4 Answers

1 1/2 story farmhouse in British Columbia

Hi, I'm looking for some thoughts on our current design for our 2000 sqft home.

Asked By Michael Blake | May 22 18
5 Answers

Difficulty finding a modulating multi-zone air-source heat pump

I need to finalize the equipment selection for my current build. My engineer along with Mitsubishi spec'd a City Multi (VRF) PUMY outdoor unit with multiple indoor units. Unfortunately, this outdoor unit does not have hyper-heat, which means that in order to meet the 99% heating requirements, it will be grossly oversized for cooling. While the compressor can operate down to low-20% of rated capacity, that is still much higher than an MXZ minimum operation for the same sized unit.

Asked By Jonathan Lawrence CZ 4A New Jersey | May 21 18
3 Answers

Vaulted / Cathedral Ceiling -- Unvented

Hi, I'm in the process of building a cabin near Saskatoon, Saskatchewan, Canada. I can't tell for sure since the climate zone map is for the US only, but I'm guessing this would be equivalent to Zone 6B or 7B.

Asked By User-7075735 | May 23 18
11 Answers

Spray foam from crawlspace onto bottom of plank subfloor in Pacific NW?

Hi there - I'm in a 1955 house in Seattle, WA, over a vented, unconditioned crawlspace, with hardwood flooring on top of plank subfloor with no insulation under it.

Asked By Frasca | May 21 18
3 Answers

Air sealing near soffit question

Hi there everyone, first time poster here. I am in the process of air sealing my attic, in addition to installing baffles so that I can add insulation on top of the existing fiberglass batts that are in between the joists in my attic.

Asked By DrJimesTooperMD | May 23 18
4 Answers

Is it worth creating a conditioned attic for my house?

I live in North Alabama, zone 3a I believe. I have a 25 year old, 1375 sq. ft. house on a slab with duct work in the attic. I have already paid a home performance contractor to seal the ceilings and top walls, add blown in insulation, and replace and seal ductwork. They also performed the door air blower test for air exchange rate. I have a bedroom that is always hotter or colder than the rest of the house.

Asked By CGFears | May 23 18
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