Community: Mechanicals

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


8 Answers

What is a minisplit’s lifespan?

A friend of mine here in Virginia (climate zone 4) heats his 1700 square foot house with a 50 gallon electric resistance hot water heater hooked to radiant coils in his floor. It is a tight, new house with cellulose between 2x6 studs. He generates 90% of the energy he needs for his all-electric house from a 6 kw solar array.

Asked By Timothy Godshall | Nov 20 17
3 Answers

Air return issue: What is best approach to diagnose why I am not getting good return flow?

House is about 3200 SQ ft. two story with a single air handler in the basement..
- (original contractor no longer living to question)
- air temp balance is hard to maintain both in summer and winter.
- Had two local companies visit wanting to add a second unit vs diagnosing existing return air paths.

Asked By BlueMTN | Nov 19 17
3 Answers

Lunos HRV system in cold climate?

We are building a 1,350 square foot single story passive solar home. Slab on grade, very well insulated, open concept living area, 2 bathrooms, 3 bedrooms. Our home is located in northwestern Ontario, Canada, with temperatures dipping to -30 degrees Celsius in winter. The winters are dry. Wondering if anyone has experience with the Lunos HRV system in a cold climate? Would there be issues with the heat exchange during cold days/nights? What about extreme differences in inside and outside humidity?

Asked By Vera H. | Jul 5 17
2 Answers

Mitsubishi 1/2 ton head not powering up

Hello, just wondering if anyone has had any issues with a brand new Mitsubishi head not powering up. I have a 5 head system that was just started today and 4/5 the heads powered up just fine with no issues. The 5th head is not being recognized by the branch box, nor will it run in Emergency Operation Mode. There is power to the line terminals.

Asked By Mike M | Nov 12 17
5 Answers

How can I address condensation in my arched cabin walls

I built a 20x24 arched cabin(Gothic arch,2 inchsteel frame, 2x4 endcaps) in 2016. We were told that the provided insulation was r-49, but subsequent conversation with the manufacturer , solar gawd, said we are more like r 30, with two layers on the outside and two layers on the inside of the cabin ribs. We planned to make the end caps r 30 but the local contractor refused to install the rigid foam we had bought so we only have r 15 fiberglass in the wall.

Asked By waterfront165 | Nov 12 17
1 Answer

How can I address condensation in my arched cabin walls

I built a 20x24 arched cabin(Gothic arch,2 inchsteel frame, 2x4 endcaps) in 2016. We were told that the provided insulation was r-49, but subsequent conversation with the manufacturer , solar gawd, said we are more like r 30, with two layers on the outside and two layers on the inside of the cabin ribs. We planned to make the end caps r 30 but the local contractor refused to install the rigid foam we had bought so we only have r 15 fiberglass in the wall.

Asked By waterfront165 | Nov 12 17
4 Answers

Heat pumps for cold climate

Is anyone aware of any conventional split system products (not mini-splits, but to be installed with a conventional air handler) available on the market with a cut-off temperature below -8C (17F)?

I am aware of the Mitsubishi Zuba central but the capacity of this product is much higher than what I need.

Thanks in advance,

Gio

Asked By Gio Robson | Nov 8 17
24 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, etc...so definitely on the tighter side for it's age.

Asked By Kjmass1 | Oct 4 17
5 Answers

Heat pump water heater—in Maine?

We are nearing the end of construction on our house. We're on an island in Maine.

The house is 2,400 sq ft., including about 600 s.f. of walk-in basement in one half of the downstairs. (The downstairs walls are ICFs with additional blueboard insulation, 2" in the basment and 4" in the finished space. There are 4" of blueboard under the slab. Upstairs walls are double studs with 11 1/2" of dense-packed cellulose.)

Our only heat sources are two mini-split heat pumps: one upstairs, one at the opposite end of the downstairs from the basement. We have a 9kW solar array on the roof.

Asked By Jason Mann | Nov 10 17
33 Answers

Another garage heating question

HI

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
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!

кроссовки дешево

ссылка

best cheap coolers