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9 Answers

I have a new home now for 8 months that has 3 stories and 1 mini split unit on each floor. I have noticed that there is an abnormally large amounts of dust in the home. I had an idea that this dust was from not having enough air movement in the home. Has anyone else experienced this or have any suggestions when using mini split systems?

Asked By Jon Lane | Jan 15 14
0 Answers

I want an externally vented microhood for my electric range. I know the Broan 40000 series is a recommended under cabinet model, but can you recommend a microwave/hood combo?



Asked By Andre Jones | Jan 18 14
6 Answers

We are installing a steel bathtub. Does it make sense to put insulation under it? What kind would you recommend? Thanks!

Asked By Daniel Herskowitz | Jan 15 14
1 Answer

We are building a relatively tight house with a balanced Lunos (through the walls) ventilation system. 2 of the bathrooms are on interior walls so they need additional (unbalance) exhaust fan that will be user controlled and turned on whenever needed. This is being vented to the roof. What mechanisms do we use to prevent cold air entering these exhaust ducts? And also, to minimize thermal bridging through the duct penetrations? thank! Daniel

Asked By Daniel Herskowitz | Jan 11 14
13 Answers

In general, what are the most efficient electric space heaters for spot heating small rooms (eg 90 sf) in a tight and well insulated home, a hydronic baseboard or a convection wall heater?

Any opinions?

Asked By Daniel Herskowitz | Jan 8 14
4 Answers

I'm building a 1,043 sq ft, 1 and 1/2 story cottage. I had independent heating and cooling load calculations done. I'm going with two Mitsubishi Hyper heats, one up and one down.

Asked By Andre Jones | Jan 2 14
1 Answer

I'm building a small house with a detached garage/apartment. I really want to go all-electric, but gas is available.

I was considering two electric tankless, but plumber is recommending single gas tankless. In reading your blog, I believe the best option now is an electric tank in the garage to serve both and a demand pump in the main house.

I want an elegant all electric solution, but I also want it to be simple and cost-effective. Which option make the most sense?

Asked By Andre Jones | Jan 2 14
2 Answers

An independent energy consultant calculated the cooling load for the first floor of my cottage at 13,778 BTUh. The heating load is 11,574. The first floor is 630 sqft, upstairs is 413 with a closed insulated crawlspace. The consultant said his calculations were conservative with the specific goal of not oversizing. I want to go with two mitsubishi hyperheat units, 12K down and 9K up.

The 12K hyperheat unit is rated for 12K BTUh of cooling. The next size up for hyperheat is the 18K unit. Will it be problematic if I go with the slightly undersized ductless for cooling?


Asked By Andre Jones | Jan 2 14
3 Answers

One of my colleagues today was telling me about how, for the last few weeks, the first three feet or so of rigid duct from the distribution port of his HRV has been covered with a thick (1/8-1/4") layer of frost.
It has been exceptionally cold here for the last month or so, so I wasn't terribly surprised to hear this.

I told him that if he was worried about it, he could set the HRV to circulate indoor air for a while until the frost dried up, then wrap the offending length of ductwork with insulation and seal it.

Asked By Lucas Durand - 7A | Jan 2 14
3 Answers

I have a two unit building and will be purchasing heat pump hot water heaters and placing them in the cellar. Each unit will likely have 2 occupants. I am deciding between buying a single 80 gallon Stiebel Eltron Accelera 300 (to share between both units) or two 50 gallon GE Geospring hot water heater (one for each unit). I was wondering if anyone had any thoughts on the best direction to go on this. Here are the points I am considering. Feedback on any of these points is welcome.

Asked By Daniel Herskowitz | Jan 1 14
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