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2 Answers


Does anyone have a recommendation for crawlspace exhaust fans?

Would an appropriately sized Panasonic be the simplest option?

Asked By Jill Neubauer Architects | Apr 21 14
4 Answers

I've been reading a lot about minisplits on here and their virtues for heating and cooling homes. I currently rent a 500 square foot storefront on the ground level of a 3 storey brick commercial building. The climate zone is 5B. The only heat is electric baseboard plus a space heater in the back workshop area. This winter I was paying $300 per month to heat the small space and with the heaters full out, it was still 15 degrees (celsius) in here.

Asked By Jonathan Dalton | Apr 25 14
7 Answers

I am exploring the utility of adding a low profile rainwater catchment system to the outside of a building. I would like to quantify the insulative value of adding a 9.5 inch water tank to the outside of a building.

Asked By Kevin Wyckoff | Apr 23 14
2 Answers

Some HRV manufacturers claim that the units can be installed in a closet. But not all closets have drains for condensate.

Do all HRV or ERV units require drains? My climate only falls below 18 -20 deg C for maybe 2 days/year. I would like to put my unit in a closet, but there is no drain nearby. If a drain is absolutely required for either HRV or ERV, then i would have to relocate it.

I have noticed that some people use PVC ducting. Could aluminum flex duct that is pulled tightly also be used (the thick stuff)?

Asked By cory b | Apr 24 14
1 Answer

Are the ductless minis that utilize a cassette unit vs a wall unit, less efficient?
Are there any drawbacks to a cassette unit over a wall mounted unit?
Lastly, can a cassette unit be mounted on a wall or is that not a good idea?

Asked By Peter L | Apr 19 14
11 Answers

So, I’ve been researching the proverbial pee-pee out of this question: dedicated ductwork for my HRV or simplified installation? Here are the pertinents:
• Climate Zone 6
• 2700 sq. ft. story-and-a-half house, along with a 2000 sq. ft. unfinished basement
• 4 Bdrm, 3 ½ bath house
• Double stud walls, spray foamed exterior sheathing and cathedral ceiling, very “tight” and efficient house planned.
• Geothermal ground source heat pump, with gas furnace back-up (Xcel Energy “dual fuel” program allowing electricity to be purchased at 40% rate for geo.)

Asked By Kent Jeffery | Apr 15 14
10 Answers

I have a humidistat sitting in my house the last few years, and have taken notice of the RH%.

I am concerned that an HRV will dry out my house too much. Location is Toronto which has cold winters (down to -18 celcius) and summers up to 30 and 35 celcius humid

With a forced air system with a humidifier installed, we go down to about 16% humidity in the winter on the coldest days. typical is around 20%-24% . In the summer we are at about 50-54% ish.

with these numbers would an HRV make it too dry, or would the numbers typically be affected only slightly?

Asked By cory b | Apr 13 14
1 Answer

Has anyone seen a review of this new HRV?

Although it is rather expensive, installation is dead easy and mechanically it is exactly what I've been waiting for for 35 years.

Consider this... when the occupants are active in the main living area, exterior doors probably get opened and closed a few times every evening bringing in significant fresh air. (This is an impossible calculation, but could be verified through measurement)

Asked By Kevin Dickson, MSME | Apr 11 14
4 Answers

Just put a Mitsubishi MUZ-GE24NA in my home. I checked the standby loss with the inside unit turned off and found that it was drawing 170 watts. I called Mitsubishi and they said it is the compressor heater and it is always on any time it is below 66 degrees.

Needless to say I'm very unhappy to have put in something in that will use around $15 dollars a month before it even produces heat.

Has anybody else had issues like this or do I have a defective unit?

Asked By Paul Lennon | Apr 8 14
1 Answer

Has anyone tried to quantify heat loss through the outdoor parts
of typical heat pump lineset installations? Does it matter much?
It occurs to me that some token amount of insulation is applied
there, but is it sufficient? Especially on the vapor line, which
runs pretty warm in heating mode and the farther the lineset goes
before coming indoors, the more it's exposed to a high delta.

Trying to ballpark it, assuming typical pipe insulation with about
a 1.5" outside diameter and half an inch thick, what is that stuff
usually, about R-3? Assume a ten-foot length running outdoors to

Asked By Hobbit _ | Apr 2 14
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