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1 Answer

Panasonic WhisperValue DC fan and TRB transfer box - anyone using these in the field yet?

For a while now I've been considering different ideas to distribute the air from my mini split to bedrooms when the doors are closed. I just noticed that Panasonic recently came out with a new DC motor version of their 3 3/8" deep WhisperValue fan, with selectable speeds (50/80/100CFM) and pretty low sone (noise) ratings.

They also make this transfer box that's designed to fit this fan (google Panasonic TRB -- I can't link anything or the spam filter gets me).

Asked By Nick Welch | Jun 27 17
4 Answers

What type of sealant?

I am retrofitting a window into a 1985 wood framed stucco house in Southern California. It has something like a grade D paper behind the stucco. I am using 15# felt to repair the damaged paper around the window opening. The window will be set on to the 15# felt. The flashed with a peek & stick flashing. So I need a tube type sealant that will stick 15# felt to a Anderson 100 FIBREX window frame.
What type of sealant should I use to set the window to the 15# felt?

Asked By Tim R | Jun 27 17
0 Answers

Non Electric Fresh Air Vents

I am considering using the Lunos type of ventilation fans which seem to require electricity all the time in order to work. Has anyone used these non-electric ventilation devices?


This is for an off grid cabin run on PV panels.

Asked By Scott Wilson | Jun 27 17
0 Answers

2 Mini Splits in one room

I just had my mini split system installed. I got multiple opinions from the installation contractor regarding the number of indoor units in one room. There is the setup:

Asked By Bryan56 | Jun 27 17
13 Answers

Drainwater heat recovery questions

Hello, I've been reading some things on drainwater heat recovery and came upon this article: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/toronto-passi...

In it, Lyndon Than says, "Leave at least a 12-inch run of straight drain pipe above the exchanger to smooth out the flow."

How critical is that? I don't have.much room to work with -- about 36" in total. I could likely get a 30" unit in that space, but if the 12" above is necessary, it wouldn't be worth the trouble.

Asked By Calum Wilde | Jun 26 17
0 Answers

Structural Masonry Joist Pocket Retrofit

I am doing a complete retrofit of a 1910 masonry 4-square. The foundation is rubble with structural brick wythes x3 for the walls. The rubble foundation terminates about 36" above grade at its lowest point. At this point, the 1st floor joists are pocketed into the brick work. There is approximately 4" of rubble ledge then 5" or so of brick penetration for the joist pocket.

Asked By Sam Onuska | Jun 27 17
8 Answers

Which ductless minisplit?

Zone 4 climate - 735 sqft - R25 walls - R40 roof - R5 windows - very tight ICF home - glazing is minimal with a low SHGC

A Manual J was done and it showed a 1 ton unit would heat/cool the home. I'm undecided if I should bump up to a 1.5 ton unit? Here are my options:

A - DuctlessAire Mini-Split - 1.5 ton - 21.0 SEER - $1,400
B - DuctlessAire Mini-Split - 1 ton - 21.5 SEER $1,060

Is it worth the extra $340 to up-size to the 1.5 ton unit?

Asked By Peter L | Jun 22 17
3 Answers

Insulation for my basement walls


Was wondering if anyone could recommend a type or place to get rigid foam for my basement walls.

The price of rigid foam insulation seems to have skyrocketed. I have 8' ceilings in my basement and about 70 linear feet of concrete wall to insulate. That's 35 2x8 sheets of dow XPS which at $42 a piece is $1600-1700 for r10. Throw Roxul on top of that to get to r24 and now I'm looking at $2500 for just insulation.

Asked By Tim-X | Jun 26 17
6 Answers

Does the insulation on this wall make sense?

I live in Madison WI and am renovating my 1927 house. I have stripped the outer walls to the studs and shiplap and have been trying to figure out the best insulation scheme. The constraints are 1. in Madison they really want plastic on the inside, and 2. because of architectural details I can't put more than 1 inch rigid insulation on the outside.

Asked By user-6832947 | Jun 27 17
5 Answers

What is minisplit short cycling? Turndown?

I understand that a "somewhat" oversized mini split will generally run at a more efficient rate, as opposed to an undersized mini split, which will run full-out, and therefore be less efficient. It sounds as if the problems with oversized mini splits would be 1) wasted money on oversize equipment, and 2) decreased dehumidification, due to the equipment not running enough. Am I about right, so far?

Asked By Ben Rush | Jun 25 17
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