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12 Answers

Are minisplits not allowed as the only heat source?

We are in Minnesota (Zone 6a). Building this summer on 12 acres. 2200 sq/ft single level (maybe a bonus above garage), slab on grade.

After speaking with the first HVAC company, they claimed that the LJ's would not allow mini splits as the primary heat source in a home. I would have to install baseboards, in floor heat, etc. They said I would be required to have a heat source in every room. I got the sense they were trying to sell me on radiant, which I have learned, I can comfortably avoid if I insulate the slab well (they also disagreed with that).

Asked By Scott K | Apr 15 17
12 Answers

TwinFresh Comfo 32 CFM Power 5 in. Single-Room Energy Recovery Ventilator

I just took ownership of the first HRV to be sold at Home Depot. I love it.

Price $475

Extra stuff I learned about it:

1. The 16cfm mode (perfect for a 2 person bedroom) is only 0.3 sones at 4 watts. Almost inaudible.

2. Low speed is 8cfm (the one person setting) is 0.1 sones which is TOTALLY inaudible.

3. It can cycle on humidity if desired. That is, it will come on when the humidity reaches 40%RH (low), 50% (medium), or 60% (high). When the humidity drops below the setpoint, it shuts off.

Asked By Kevin Dickson, MSME | Jun 6 14
0 Answers

HTP Crossover Wall or Phoenix LD?

I'm looking at my options for a combination water/space heating appliance. I'm liking the look of two HTP units that are completely different in operation, the Crossover Wall and Phoenix LD.

The Crossover Wall is a combination on-demand/tank heater with a small tank, 10-1 turndown and either 150k or 199k BTU ratings. The Phoenix Light Duty is a conventional tank-type water heater with condensing burners, 3-1 turndown and 76k BTU input. Both are very efficient, though feedback and reviews are limited. The Phoenix LD has some positive reviews, but relatively few.

Asked By Lance Peters | Apr 17 17
4 Answers

Effect of spray foam on AC refrigerant lines & electrical wiring

Finally we are ready to make our attic a conditioned space. R38 on 2x6s and R21 gable walls. The new closed-cell Demilec HFO looks very promising. After all the research, I’m done to one major concern:

Asked By David Goldman | Apr 11 17
0 Answers

Fujitsu minisplit installer in Orangeville, Ontario?

I am looking for an HVAC company to supply and install a Fujitsu AOU48RLXFZ1,etc in our new high efficiency home in the Orangeville, Ontario area.

So far no joy in finding a Fujitsu authorized company to do the work all those I've contacted will not travel beyond their local areas (ie - Toronto, Barrie, etc)

Can anyone recommend an installer for me?



Asked By Steve Babcock | Apr 11 17
2 Answers
3 Answers

Comfort considerations in placement of ventilation supply registers

We’re trying to decide where to locate the fresh air supply registers for an ERV-based ventilation system. Duct length and placement is one consideration, but what about comfort considerations? We’ll have cool air blowing from these in the winter, and we’re trying to minimize any discomfort from that. I’m especially curious about the experience of others who have lived in houses with ERVs or HRVs and separate ventilation ductwork.

Asked By William Costello | Apr 7 17
6 Answers

Is the Panasonic Intelli Balance 100 ERV a reasonable new construction DYI project?

The Panasonic Intelli Balance 100 ERV seems to be rather new on the market, and I am looking for information on ease of it being a DIY installation project during new residential construction.

Asked By Nina in CNY | Mar 10 17
8 Answers

Using mini split systems on large open spaces

I know there seems to be a millions suggestions on line for using mini splits to heat, cool, do your laundry etc. However, as much as I have googled, and my GoogleFoo is strong, I have found almost no discussion on how to heat and cool large open spaces with mini splits.

So my situation...

A large-ish room, 62x36, or roughly 2200 sq feet, 15ft ceilings (upstairs floor). (Shop / Work space ) The long side faces east west, short sides south and north. Solid brick walls, think late 1880's construction, 18" thick. No western exposure, blocked by another building.

Asked By jtkilroy | Apr 5 17
21 Answers

Creative, efficient and low-cost radiant cooling system?

I've probably asked this before and I apologize if this is a repost...but I'm looking to rig some infloor cooling to my house.

Living in Northern Canada we don't get many "hot" days, but for 3 weeks of the year it would be nice to reduce the temp by a few degree's.

The house is 100% radiant heat with a Viessmann boiler and indirect Viessmann Stainless Steel Domestic Hot Water system.

Asked By Mark Helmrich | Apr 4 17
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