Community: Mechanicals

[Click map to enlarge]

Please register for a free account or sign in to ask and answer green building questions. The usual rules of courtesy apply: 1. Be nice. 2. If you can't be nice, be polite. 3. If you can't be nice or polite — well, please be brief. To attach a photo or illustration: Under the box labeled "More explanation," look for the words "File attachments." Click that, and you should be able to attach a photo. Thanks for joining the conversation!

2 Answers

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

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

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 25 14
2 Answers

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

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

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

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
6 Answers

I am playing around with possible scenarios for my HVAC setup in the house I am planning to build. One possibility I am really looking into is that of not using any ducts. I'm not certain why I am so opposed to having ducts, but I think it has to do with the idea of blowing dust around, having drafts, and general complications - even if the ducts are straightforward, it seems like equipment connected to ducts tends to be complicated.

Asked By Stephen Youngquist | Jun 30 14
2 Answers

All,
We just purchased a small, single-level ranch with electric baseboard & wood stove for heat. The hot water is currently a propane 50 gallon tank in the laundry room, which is about 10'x5'. With the dryer going, the worst-case depressurization fails and potentially back-drafts the atmospheric draft hot water heater. The current water heater cannot stay, and there is no where else to locate it. The crawl has no inefficient source of household heat, and is only 4' tall, less the joists.

Asked By Bob Rueter | Aug 25 14
19 Answers

So, My AC system died last spring, and I was prepping to put new windows (impact resistant, low e) in my house... My house is approx 2200 sq.ft in Florida, south of Tampa... Zone 2A

I had a 4 ton system, and knew that would be too big as a replacement, but my HVAC tech replaced it with what was here and said he could tune it... Now my house averages 55%rh or higher... Up into mid 66-67...

Asked By Chris Marriner | Aug 18 14
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!