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4 Answers

Is 170 watts normal for compressor heat?

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?

In Mechanicals | Asked By Paul Lennon | Apr 8 14
2 Answers

Roxul and basement wall dynamics

The envelope is pretty good these days and adding more polyiso to
the inside of the basement wall has helped with overall heat loss
a little more, but I think there's still something going on in the
cinderblock wall that's affecting slab temperatures near the edge
and I wanted to float an idea for how I can better deal with that.

This is long, but one needs to understand the background and present
setup. Executive summary: should I insulate just the above-grade
exterior part of a foundation wall with Roxul panels?

In Green building techniques | Asked By Hobbit _ | Apr 7 14
4 Answers

I'd rather put 2" of rigid foam on the interior of the rafters than on top of the roof deck.

I have 2x12 rafters and was planning on insulating with dense pack cellulose or rock wool for a cathedral ceiling. Then putting rigid foam on the inside , then drywall. Does this make sense? I was hoping not to vent. Will this work.

In General questions | Asked By Seth Kelley | Apr 6 14
6 Answers

Why are my Willmar Windows (Jeld-Wen) sealed glass units repeatedly failing?

Subject: Willmar Windows Jeld-Wen Ontario Canada

In 1997 we purchased 78 top of the line windows and doors from Willmar Windows, a division of Jeld-Wen. These were "R+10 with Heat Mirror, Metal Clad Wood" windows and doors.

Since the first year there has been a steady rate of seal failures. In 2004 Willmar decided to replace all of the glass units. In 2007 Willmar finally accomplished this.

They were replaced with glass units called Tripane T2SA with "Triple Solar Shield, 2x Low E and Argon". Since 2007 we have had 12 seal failures in these units.

In General questions | Asked By Jane Gray | Mar 30 14
12 Answers

Converting from oil heat & electric hot water to geothermal and redesigning utility room and master bath

I am moving from Southern California, where I typically don't heat or cool my home to Central Pennsylvania.

The home I am purchasing has Oil Forced Air Heat and Electric Hot Water and appliances.

There are no Natural Gas Lines near the home - so Natural Gas is not an option.

In Energy efficiency and durability | Asked By Jennifer Hogan | Apr 6 14
8 Answers

Insulating unvented cathedral ceiling

I bought a house with a vaulted ceiling. Drywall is nailed to 2x6 roof rafters. It is unvented for the most part. I have no idea what kind of insulation is up there. I want to insulate it but don't want to tear off the roof (which is relatively new), or the ceiling. There are big overhanging eaves that can be opened to look up into the cavities. I'm wondering about my options here. Is it possible to spray closed-cell foam up from the eaves and fill the space? Any suggestions?


In Energy efficiency and durability | Asked By Robert Jones | Oct 16 09
1 Answer

2012 IECC - Slab-on-grade Zone 4B

I will have an ICF stem wall that will transition into the ICF house wall. The interior will be a slab-on-grade design. This is for a Zone 4B (desert) climate.

1 - Should the vapor barrier be on-top or below the rigid EPS?
2 - What thickness is good for a vapor barrier?
3 - Will 3" of rigid EPS suffice for a Zone 4B climate?
4 - Any links to some details showing the above condition?
5 - Should crushed & compacted rock be used below the EPS and concrete slab?

In Green building techniques | Asked By Peter L | Apr 8 14
1 Answer

New construction sealed crawlspace R-value and air exchange question

In climate zone 2 what is the required R value if doing sealed crawlspace and insulating foundation walls instead of floor? Table N1102.1 lists crawlspace walls. Is this for sealed and when not insulating the floor? That value is 0 for my climate zone. Is that accurate or is that for vented?

2nd question:
Should an air exchange (in addition to air supply to crawlspace) be installed in the above scenario? I think the code asks for it but I read somewhere (possibly on here) that the positives are outweighed by the negatives. Is that true? Is it preferable to not install that?

In Building Code Questions | Asked By Chris Purvis | Apr 7 14
4 Answers

The most value-engineered siding furring strips over thick rigid foam... but what width?

Assuming labor is free, I've found that the cheapest furring strips would be 15/32" plywood. It's quite a bit cheaper than 1x4's (less than half the price, close to a third, if ripped to 2.5"), and can be narrower than 3.5" without worrying about splitting like 1x3's or 1x2's would. Also, it just barely meets the 7/16" penetration requirement that James Hardie has.

In Green building techniques | Asked By Nick Welch | Apr 4 14
24 Answers

Are code-breaking BPI builders causing trouble for unvented roofs?

I have a flat unvented roof on my 100-yr old rowhouse in Philadelphia, climate zone 4. There is about 18" between the top of the ceiling and the bottom of the roofdeck. I'm looking at my options for air sealing and insulating this roof--there is currently no insulation at all.

In Building Code Questions | Asked By Andrew Levitt | May 4 11
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