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60 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

Asked By Dave De C | Jul 16 16
9 Answers

How should I heat my water?

Hi there. I'm just starting a major renovation of a two story studio space attached to our detached garage to be used as a studio and sometimes guest house. We're adding water and septic to the house, and I'm looking for ideas on the best way to get hot water. We'll only have a single bathroom with shower, and a small wet bar sink on the same wall as the bathroom, so there are no long pipe runs. Usage will be infrequent but once in a while fairly aggressive if we have guests there who need to take multiple back-to-back showers.

Asked By Curtis M | Jul 17 16
7 Answers

Solar Water Behind a Window

First a quick back story: I live in Halifax, Nova Scotia, which to my knowledge is zone 5...? I'm getting condensation on my cold water pipes, where the pipes first enter my house from my well. In another question about this issue, Charlie Sullivan was kind enough to offer a suggestion of using a drain water heat recovery unit to preheat the cold water. Which, really is a great suggestion as it's 100% passive.

Asked By Calum Wilde | Jul 21 16
3 Answers

Net zero is not expensive?

I'm having a home built and am trying to go net zero with PV and an all electric home. The solar guy and some contractors are very surprised when I say it can be done with 4 kw of panels and fairly standard construction and heating system. I'd like to run my numbers by the wise advisers here and you can tell me if I'm wrong.

Asked By Brad H | Jul 20 16
33 Answers

Direct vent vs. power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
4 Answers

Insulating cold water pipes

I'm getting a lot of condensation on my cold water pipes. The house is plumbed with pex, and most of the condensation is collecting on the copper and/or brass fittings.

Asked By Calum Wilde | Jul 20 16
3 Answers

Alternatives to MHK1 for minisplit?

We've had a three-head Mitsubishi Mr. Slim system for about a year now, and we've noticed that it takes a fair bit of fiddling to get the unit to hold a set-point. The necessary offset in heating mode is something like 8 degrees F, varying with the outside temperature. During the shoulder seasons, it seems like we pretty much have to cycle the unit off and on or it will overshoot.

Asked By Logan Schmaltz | Jul 13 16
14 Answers

Does anyone have experience with Zehnder ComfoFlex?

We are building a new house and in the final stages of design. The design includes an HRV and Zehnder ComfoTube looked great until I discovered that it is not UL listed. So, I'm curious if anyone can provide feedback on ComfoFlex. There isn't much on the intertubes...

Asked By Trevor Fontaine | Feb 9 16
10 Answers

How efficient are recirculating kitchen range hoods with carbon filters at removing air pollutants from cooking?

I looked at a few of these filters for the recirculating range hoods and they didn't look all that impressive, but maybe I am looking at the wrong hoods. If passive houses are using recirculating hoods how well are the hoods actually working. Clearly there is a tradeoff for energy efficiency and range hood function. Is there any specific data on this? Are there certain types of carbon filters that work better than others? I am not talking about removing moisture or CO from gas ranges but more grease and other pollutants produced when cooking with electric ranges and ovens.

Asked By Dillon Vautrin | Dec 16 15
32 Answers

Desperate help, minisplit sizing

I'm a GC building my own home. I live in an extremely rural area with very few knowledgeable hvac professionals within 300 miles. I have decided to go with mitsubishi ductless mini splits to heat and cool the entire house. Basically I need help choosing what size units to purchase, how many heads, and to me most importantly where to place the units. This home will be occupied by just me and the wife so interior doors will be open most of the time.

Asked By aaron miiller | Jul 13 16
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