Community: Mechanicals

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8 Answers
4 Answers

Ventilation ducting advice

It looks pretty likely I'll be running my own ducting, as I have been left with a supply of specialized duct pipe and distribution accessories after my main builder turned into a ghost. I understand the basics, but some of the details I'm not sure about. I have 13 distribution boots, and it's pretty clear the intent was to have 3-4 exhausts, and 9-10 supplies. Two bathrooms and the kitchen obviously need exhausts. He actually installed half of the boots, and I notice he put two in the large living area, at opposite ends. Should one of those be an exhaust, or should they both be supplies?

Asked By Trevor Lambert | Feb 16 18
18 Answers

ERV recommendations

Hi, I need to make a fairly quick decision on an ERV. The house build is many months behind schedule, and the builder has fallen off the map so it looks like this part of the project I may have to contract out to someone else. Before the builder disappeared, we were in line to get a Jablotron Futura (formerly Air Pahoda). They really pushed this brand, and I'm embarrassed to say I didn't do any research in ERVs, so I don't even know for sure it's any good (we were told by them it's the best, the reasons for which I didn't delve into, again to my discredit).

Asked By Trevor Lambert | Feb 13 18
8 Answers

Are ductless minisplits a viable solution for a 200-year-old timber frame retrofit?

Project type: full house renovation; currently down to the stud.
House type: 200 year old timber frame style farmhouse
Location: Milton, NY, USA

We're in the midst of a full-house renovation of a building that sat vacant for 20 years. We replaced the roof and applied closed-cell spray foam in the attic and gable wall extensions. The intention is to closed-cell insulate the remained of the building envelop upon completion of MEPs.

Asked By User-6952768 | Feb 13 18
1 Answer

Whole-house fan in cathedral ceiling design

I'm building in climate zone 6B and I'm trying really hard not to put in AC. Our house is at 7000ft but we still get a few weeks of hot temperatures that are bearable during the day but are too hot for us to sleep at night. My thought was to do an air flush in the evening using a whole house fan.

Asked By Steve Mackay | Feb 13 18
7 Answers

Recommendations on HVAC Design

Because local HVAC contractors typically oversize and aren't apt to land on the ideal solution for high performance homes, I am considering analysis by a third party like Energy Vanguard for my cold climate ductless heat pump system:

https://www.energyvanguard.com/service-category/hvac-load-calculations

I would like to get some feedback on services like this and any recommendations of alternatives to them. I was quoted $900 for:

-Manual J room-by-room heating and cooling load calculations
-Manual S system specification with Diamond System Builder report for Mitsubishi

Asked By J M | Feb 13 18
3 Answers

Heat pump for a remodel - Questions for a remodel in a Marine (3C) zone

Thanks for your thoughts in advance!

I've been reading everyone's comments and so many articles to come up with efficient ideas for an impending remodel, and I'm curious what others think at this point.

I'm in zone 3C (Marine), and the ocean moderates the climate in my neighborhood so heavily that it's always slightly chilly, but never freezing. No one installs air conditioning.

Asked By Dirtfox | Feb 12 18
2 Answers

Minisplit quantity and location

My name is Sam. This post may not come through with my name (as past posts have not) and I cannot find a way to add it!

I am looking for advice on heating systems for a 1000sf addition on a 1922 home in Seattle. The addition will share one wall with the existing structure, and I have attached a floor plan. Everything new is black, existing is gray.

The existing house is as insulated as one might expect. 2x4 walls and roof--not a lot there and far from airtight. New structure will be R-21 wall cavity insulation. Roof will be unvented with R-30 plus R-10 rigid above sheathing.

Asked By User-6965270 | Feb 12 18
7 Answers

Has GBA made me excessively demanding? Are these details OK?

Climate zone 3A (Mixed-Humid)

Took a look at a new 3-story townhome development and I'm curious to know if these HVAC/construction details are "ok" or potentially a serious problem.

Photo A: This is a shot of the duct work on the first floor (Living, Dining, Kitchen). It appears that the construction designer didn't leave enough room and floor truss height is too low. Does this duct design look problematic?

Asked By John Clark | Feb 11 18
10 Answers

House next to deep rock quarry: How can I tap water below 12-16" of ice for heat?

We have 50' deep water 50' behind our house.Water is very clean with 20' visibility at least-comes from limestone rock --no creeks or rivers--it is a hole in the water table. 8 acres. we have only 48" of earth above flat limestone shelf that is entire area around us. It was a Quarry for limestone way back. the water is at top of shelf--about 48" below the yard.

My minisplit is outside in 20 degree winter air while its 32 degree's or above a short distance away?

Asked By Scout159 | Feb 10 18
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