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6 Answers

Ductless Mini Split Heat Pump - Mitsubishi 9000 BTU vs Daikin 12000 BTU vs York 12000 BTU

We received multiple quotes to get a ductless mini split installed, and wanted to know what everyone thought was the best option. We live in Seattle, where the weather is mostly mild except for a few days in the summer/winter. House is small at only 740 sq ft, and mostly open. We'll also have our electric furnace in the case we need a backup and possibly put in wall heaters in the bedrooms. These are in the order of highest quote to lowest quote with a difference of about $900 (Installed) from Option 1 to Option 4.

Option 1: Daikin 12000 BTU 23 SEER

In Green products and materials | Asked By Gina Chung | May 23 14
3 Answers

Ductless mini split sizing advice - Mitsubishi specific

We are going to have a Mitsubishi heat pump installed in our house (in progress) soon and would be interested in some thoughts on sizing.

The house is in Jackson, NH 03846 (climate zone 6a). It's cold and snowy, but we have great passive solar gain, open floor plan, tight construction, and high insulation values. We have wiring in place for regular electric resistance backup. Our Energy Star rater calculated our heat load at 11.2kBTU / hr at design temp (-6F, 65F inside, based on St Johnsbury VT).

Looking at the new Mitsubishi FH line, MSZ/MUZ units:

In Mechanicals | Asked By Brian Post | May 23 14
2 Answers

Jeff Wager has completed his Passivhaus documentary

Documentary filmmaker Jeff Wager has completed his Passivhaus documentary. When it was being edited, the film had a working title of "Balancing Act." However, the completed film has been titled "Superhouse."

The film includes interviews with many experts who are probably familiar to GBA readers, including Chris Benedict, Wolfgang Feist, Henry Gifford, Robert Hastings, Martin Holladay, Mike Kernagis, Katrin Klingenberg, Ken Levenson, Bill McKibben, Chet Pasho, Peter Schneider, Barry Stephens, Stephen Thwaites, Michael Welch, Alex Wilson, and Li Ling Young.

In General questions | Asked By Martin Holladay | May 27 14
8 Answers

Multi-head low-temperature minisplit?

Has anyone seen a extra low temp multi head mini split offered. I got quoted a Fujitsu 12RLSH but was told that the extra low temp heating models, supposedly still offering heat to -15F, was only offered as a single condenser and air handler.
I am building a three bedroom ranch in Northern NY, my heat loss is around 21,000 BTU/hr.
The floor plan is mostly open but the bedrooms are on opposite sides of the house and might have doors closed.
I will have backup electric baseboard but would like to have cooling in the rooms so I was looking into a multi head system.

In General questions | Asked By kye ford | May 23 14
10 Answers

Q&A map should show climate zones in Canada

Please add a Canadian map in the Q&A section header.

[Editor's note: Here is a link: Climate Zone Map Including Canada.]

i believe that there are enough Canadian users/members to which it would be useful.

i also look at the USA map often when reading stuff from US members to understand
their situation. Probably reverse happens also.

Show some respect! ( always wanted to type that ..ahhaahah )

Neway you guys down will probably want to know in which zone is the Stanley cup residing this year, next year and so on ... :p

In General questions | Asked By Jin Kazama | Feb 26 13
1 Answer

Here is a climate zone map that includes Canada

Finally found a map that is worth looking at and includes most of Canada .

Now you have no reasons not to add this one somewhere on the site :p

http://www.greenzone.com/media/images/original/181.jpg

In General questions | Asked By Jin Kazama | May 26 14
14 Answers

ERV or Central fan integrated ventilation best for hot humid climate?

I read an article by Martin Holladay who said ERV could actually make the situation worse in hot humid climate during those days when temp and humidity level are mild. That confused me. I would appreciate answers to questions about the best vent. system for a new build air tight house at approx. 2200 sq ft, in zone 3A below the red line. Heat pump HVAC system.
1. Why might an ERV make matters worse on mild days with low humidity?

In Mechanicals | Asked By rob clark | May 23 14
8 Answers

Insulating under footings?

Hello, I'm building a house for my parents in northern British Columbia. We are shooting for a superinsulated and air tight building. It's will be a story and a half, on an ICF foundation crawl space.

Planning on doing the GWB, 2x6 (structural/utillity chase, with either dense-pack cellulose or rock wool batts),1/2" ply (taped to become the vapor/pressure boundary) with a 12" Larson truss on the outside of that (dense-pack cellulose), then WRB, rainscreen, Hardiplank.

Planning on beefing up the ICFs with 6" of EPS on the outside, with also 6" of EPS under the slab.

In Energy efficiency and durability | Asked By Richard Alton | May 17 14
6 Answers

Hot water heater strategy

Been thinking about the best way to set up my hot water heater system and wanted to bounce my idea past the readers of GBA.

Zone 5A - Central Illinois. Water heaters will be located in basement. Family of 5 (3 young kids) with plans to accommodate elderly parents if necessary in the near future.

HVAC system is a 3-ton GSHP with desuperheater that can provide some water pre-heating but not enough to meet DHW demand by any means.

In General questions | Asked By Robert Kohaus | May 22 14
10 Answers

Where the heck are the podcasts?

I can't seem to find the podcasts anymore. Could someone please direct me to the list of what's available and how to get them? Thanks - Jim

In General questions | Asked By jim blodgett | May 22 14
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