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32 Answers

HVAC options?

I need some help with HVAC planning for a duplex I am currently looking to build. It will be located in South West Manitoba aka Zone 7A from looking at the map.

I have a couple of options...
1) Stick built on site. This would give me the option of a slab foundation aka hydronic radiant heat.
2) RTM moved onto crawl space foundation. This would not allow for hydronic radiant unless I attached the lines to the underside of the RTM flooring (not inside a slab).

Asked By R Yan | May 12 15
14 Answers

Minisplit heat pump sizing issue

Hi All,

I am hoping someone can point me in the right direction.
We are thinking to add mini split ductless heat pumps to our existing 1550 sf raised ranch in Manchester NH. The house has good insulation for the age with R50 in the attic and 15 year old windows. It has 2x4 walls so not sure about R-value there. Currently have hot water baseboard heating system with 25 year old oil fired boiler and our oil consumption averages about 450 gal / year.

Asked By Alex Frost | May 13 15
10 Answers

Backup heat for mini-splits? Electric cove heaters?

I'm planning a house build and am seriously considering using mini-splits. The house will be in climate zone 7 with a -13F 99% design temperature, so I want to make sure I have a source of backup heat when the mini-splits turn off during really cold nights (-25F happens several nights a year), and also to make sure the bedrooms stay warm enough if the doors are closed.

Asked By Nick Hall | May 15 15
52 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

Asked By Justin Fink | Aug 22 13
21 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!

Asked By Shaun Kennedy | Sep 11 14
1 Answer

Ducted and ductless heads on a zoned mini-split

I performed an energy audit for a homeowner who is interested in a zoned mini-split system.

My question is whether a ducted indoor unit can be used in, say, a master bedroom suite, while a ductless indoor unit can be used in a different zone but with the same outdoor unit; or do all zones have to use the same type of indoor unit -- all wall mounts, all floor mounts, all ceiling insert, etc.?

My second question is whether different zones can use different-btu/h indoor units (e.g., small family room gets a smaller indoor unit than a large living room, etc.).

Asked By Jason Owsley | May 13 15
15 Answers

Geothermal - Sizing Issues - 4 Ton or 5 Ton?

I live in Cincinnati, OH and I am zeroing in on purchasing a geothermal heat pump for my 5800 SF (conditioned) home. My home is all electric is currently heated by an 8 year old 4 ton air source heat pump with 15Kw electric backup. My issue is the two geothermal companies I have contacted to quote the job disagree on heating load of my home. Both companies did Manual J calculations, but are coming up with different numbers. One company has the heat load at 55k BTU -- says a 4 ton is the way to go. The other company has heat load at 68k BTU - says go with a 5 ton unit.

Asked By joel perrine | May 3 15
6 Answers

What's a good damper for a bath fan/range hood vent?

My bath fan vent is basically a big hole in the house to the exterior and sucks air out of the house in the high New Mexico winds, which today reached 30 mph. There's no damper or air check valve or anything like that installed up there, and I'd like to rectify it. What do people use for this situation? A standard butterfly damper? Something louvered? This thing? http://www.batticdoor.com/bathfandraftblocker.html

Asked By Nathaniel G | Nov 23 14
3 Answers

Thermal break and insulation for gas fireplace flue pipe

We are building a tight and well insulated home in WY. It gets very cold here. We are paying special attention to creating a thermal break and insulating all ductwork to the exterior. They installed a "one pipe" gas fireplace and the metal flue pipe comes straight from the outside with no thermal break. I am told that it must have one inch of air around it so we are not able to insulate the pipe. I had suggested stove pipe insulation which is fire proof but contractor says code does not allow anything.

Asked By John Culbertson | May 4 15
5 Answers

Need help puzzling through the details of outfitting my house with a mini-split system

Right now my house has a 19 year old 125,000 BTU 80% efficiency gas furnace with ducts in the unconditioned attic, partially buried under insulation. I'd like some help determining if mini-split heat pumps will work as replacements, and in what configuration.

Asked By Nate G | May 2 15
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