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80 Answers

Geothermal nightmare

We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.

In GBA Pro help | Asked By Colleen Nicholson | May 30 13
22 Answers

Air Scrubber Plus

I am considering installing an Air Scrubber Plus system on Zone 1 for my house. I have a coworker who has installed one and says it has worked great for treating indoor air (particularly cooking smells). I was curious if this system is worth the money? Is it worth it given the lifecycle cost - replacement of the bulb (almost as much as the system)?

Just looking for anyone who knows more about UV bulb filtration, the risk vs. reward, and in particular about this manufacturer and their product.

The link to the air scrubber plus is here: www.airscrubberplus.com

Thank you!

In Mechanicals | Asked By Shaun Kennedy | Sep 11 14
1 Answer

Good non-venting range hood?

I'm looking for a non venting hood for tight house with HRV exhaust in kitchen. Range is electric. Any ideas?

In General questions | Asked By Ben | Jan 5 16
1 Answer

Anyone have any experience with a low GWP closed-cell spray foam?

Wondering if anyone has had a low GWP [global warming potential] foam installed in their construction product, and what product they used? I have done a little research on Icynene's ProSealEco closed cell foam. Any one have anything good or bad to say about the stuff?

In Green products and materials | Asked By Cameron | Jan 5 16
11 Answers

I have a new home under construction in NE South Dakota (cold Zone 6)

I have a new home under construction in NE South Dakota (cold Zone 6). Exterior walls are 2x6 with 1/2" 5-ply plywood.

My insulation contractor will be dense packing cellulose in the walls. He uses a 6 mil polyethylene for the netting. My concern is the netting is a vapor barrier, allowing very little wall drying to the inside, only to the outside. Your thoughts and comments would be appreciated, Thanks.


In General questions | Asked By Matthew | Jan 4 16
10 Answers

What's a cost-effective way to ventilate while maintaining winter humidity in a cold and dry climate?

I live in the high desert, and it gets cold in winter (there's some snow on the ground right now) but remains very very dry all the time. I've done a lot of air sealing work in this old house (last blower door test 5.2 ACH50) so that now, finally, when I keep all the windows closed and don't run the bath fan, the humidity naturally climbs to a comfortable 35-40%. However, with no mechanical ventilation, the CO2 level quickly climbs to over 1200 PPM and continues rising, so what I do to keep it down is turn on the bath fan.

In Energy efficiency and durability | Asked By Nate G | Jan 5 16
5 Answers

Mitsubishi multi-zone Hyper Heat models: true minimum output?

Take MXZ-8c48nahz as an example - the submittal indicates that the mitsubishi heating capacity goes from 7200 Btu/h to 54000 Btu/h for DB temperature over 5F. The NEEP spreadsheet with far more detailed spec indicates that the minimum is 27000 Btu/h instead.

Am I looking at two completely irrelevant number? If not, which one of this is the true minimum output capacity?

Thank you.

In Mechanicals | Asked By Anonymous | Jan 5 16
20 Answers

Attic moisture ...


I have read the articles on attic ventilation and moisture and believe I understand that at its core any attic moisture is typically the result of air leakage from the house and/or basement/crawlspace moisture.

Zone 5A.

In Energy efficiency and durability | Asked By Justin Brown | Dec 30 15
2 Answers

Mitsubishi 18,000 BTU Heat Pump Boiling/Bubbling Sound?

About one year ago I purchased a Mitsubishi 18,000 btu heat pump. It is the low ambient heating version...FE series i believe not the GE. Last winter was brutally cold (northeast pa) and never had in issue. Just last night it dropped to about 7 degrees F. For the first time I noticed a bubbling/boiling sound coming from the line set and primarily the indoor unit. Like I said earlier, I had subzero temps last winter and never heard this noise. The heat pump continued to deliver warm air and my home never got chilly. I've always heard if ain't broke don't fix/worry about it.

In GBA Pro help | Asked By Matt Noll | Jan 5 16
5 Answers

Water dripping from air conditioning supply vents

Hello I thought I had figured this out pretty easily the first time I noticed it.

There was a small puddle at the corner of my bed that I though might have been one of my lovely male pups leaving a present. As I was going to clean it up, I got hit with a drop from the air conditioning vent in the ceiling.

I chalked this up to my wife taking a shower in the master bath without running the fan. We tend to have higher humidity in our master bedroom because my wife prefers the door shut and rarely uses the bathroom fan during showers. I figured some warm moist air condensed.

In GBA Pro help | Asked By Mike M | Jan 5 16
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