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44 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
5 Answers

Should I go with a ground-source heat pump or PV-powered electric boiler?

I have a 1940's Cape Cod (1200Sq Ft) along the shoreline in Connecticut (Last bill was 294KWH cost $64.09). I want to ditch oil and swap to a new boiler for my hot water cast iron radiators. The overall plan is to add a functional 2nd floor and become a colonial style home, and make vast improvements to the insulation, windows, and air sealing in that process. I'll be demolishing the chimney as a part of adding on the second floor so I need to get a good heating plan in place before I start executing the building/insulation/windows plan rolling.

Asked By Kevin Dingle | Sep 5 14
32 Answers

HRV with bathroom exhaust fan

I asked this question in the comments of an article, but thought I would have more luck here...

I am installing a LifeBreath 155ECM HRV in a new home. It will be exhausting air from 3 bathrooms spread across 2 stories. The HVAC sub is recommending installing separate bathroom exhaust fans for local exhaust (shower moisture, odor, etc.).

Asked By Chris Harris | Sep 20 10
2 Answers

Hydronic solar thermal?

Has anyone ran across a design guide for passive solar thermal heating and cooling using water-antifreeze as mass in pex metal radiant roof and/or floor-wall lines? I’m thinking solar thermo-siphon vs a mechanical pump.

Asked By Terry Lee | Sep 1 14
1 Answer

Nyle Geyser RE problem

I've seen the Geyser RE mentioned on this forum numerous times, so I am hoping someone can help me troubleshoot my unit. I installed one this summer, connected to a new 80 gallon State electric water heater. It worked for a couple of days and then starting tripping the circuit breaker. It was a 15 amp circuit (I was using a 25' 12 gauge extension cord to reach it which tech support had ok'd beforehand). I thought maybe the combo of a 15 amp circuit and the extension cord was the problem, so I wired a new dedicated 20 amp circuit right next to the unit, but the problem persisted.

Asked By austin jamison | Aug 28 14
12 Answers

Are minisplits a good solution for heating (and cooling) a smallish addition to my 85-year-old house?

I'm in zone 4 (NYC suburb) and the original house is a 2 1/2 story wood framed house heated by gas fired one pipe steam. Cooling is from window units. Our addition (currently rough framed and dryed in) is two stories with an 18' x 15' exterior footprint. 3 foot block stem walls make the lower level slightly smaller than the upper. The upper level, which connects to our main floor, will be our new kitchen, and the lower level, which connects to a walkout basement, will be a play/TV room.

Asked By mike mcguirk | Aug 24 14
2 Answers

How do I balance a Zehnder Comfoair 350?

I recently installed this model Zehnder HRV, and now need to learn how to balance it. The manufacturer's installer manual is too brief on this procedure to be helpful. Is there anyone out there who can anyone give me the detailed procedure on how to balance this HRV?

My main concern is to ensure the intake/exhaust is balanced and that I am not pushing too many CFM's into/out of the house. I don't care too much about getting each room's cfm perfect at this point - since I'm going to be continuing to renovate the house. I just don't want to be pushing moisture into the walls right now.

Asked By Matthew Robinson | Aug 27 14
4 Answers

Thermal break for new radiant slab?

We are retrofitting a slab on grade portion of our home that has an existing 4" thick concrete slab with a thinnish layer of insulation underneath. We are going to install radiant heating over top of this existing slab. There's an existing fireplace in the room and the hearth is 3 inches above the existing slab.

So to keep the new radiant overall thickness to roughly 2 1/2 inches to allow for 1/2 inch for wood flooring I was going to install 1/4 inch thick extruded poly (Owens Corning fanfold) then Hilti wire mesh, then 5/8 tubing, then gypcrete.

Asked By chris hoy | Aug 26 14
6 Answers

"Barometric damper" air inlet for room with woodstove

Wondering if someone can identify a specific product for this application. The merits of the application might entice some to debate, but I am neither a code writer nor building inspector, just a guy caught between them.

I have a job with a woodstove in an art studio space. It does not have a direct connection from the firebox to an outside air duct, and it would be difficult and costly to accomplish that, because the stove is on a concrete slab, it is against a wall with a garage on the other side, and it's 12' from any exterior wall.

Asked By David Meiland | Aug 26 14
6 Answers

HRV retrofit for a basement

I live in North Vancouver, BC, marine zone 4/5 and am renovating an older home.
The basement was finished years ago as a suite, to about R30 so I am not interested in redoing it.
The problem is we don't have enough ventilation in some of the rooms due to the fact that it is mostly a direct vent gas fireplace heating it.
Cold air returns are virtually non existent.

I was thinking of installing an HRV to provide more ventilation.

The spaces in the basement are a bedroom, bathroom, laundry room, a kitchen/living area and a separate family room.

Asked By Aaron Gatzke | Aug 24 14
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