Community: Mechanicals

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0 Answers

Manual D spreadsheet examples?

Hi, I'm looking for any completed examples of the Manual D spreadsheet which is given out free from ACCA:

Thanks to this site for educating me on the importance of Manual J and D calculations. I know there's software for this but a) I'm cheap, and b) I'm a nerd and like to get into the details.

My hard copy of the manual is in the mail and while I wait I'd like to figure out the sheet as much as possible.

Asked By Jonathan Dalton | Oct 1 14
14 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:

Thank you!

Asked By Shaun Kennedy | Sep 11 14
12 Answers

Should my indirect hot water heater have a mixing valve?

I have a 2300 square foot colonial, built 1960 in Massachusetts (Zone 5A), with three zones of fin tube baseboard. There's a 75 gallon whirlpool tub which we almost never use; the two showers are fairly low-flow. Heat loss done by was 55,840. I use town water, which is very good quality (Quabbin reservoir). I've accepted a bid to replace my heating system with a Lochinvar WHN-85 boiler and SIT40 indirect water heater.

Asked By Daniel Griscom | Sep 15 14
13 Answers

Retrofit heating system

We recently bought a second home in the Catskills, which was built in the 1930s. Current heat system is oil furnace forced air with a pretty new high end furnace. We had an energy audit done and found that the house was not well insulated at all and are in the process of takin advantage of energy efficiency programs to upgrade.

Asked By Carole Florman | Sep 15 14
0 Answers

Beware the dual-hose portable AC / heat pump

For years I've wondered if a dual-hose portable heat pump/air conditioner could be a poor man's ductless minisplit heat pump. The advantage, as my logic went, was that I didn't have to drill any holes or charge any refrigerant.

I bought a 14kbtu portable heat pump (Edgestar AP14001HS Portable Air Conditioner) ($400-$700)

I did some primitive temperature and airflow measurements.

I was impressed by the overall quality and the 11.2 EER, but what I found was very disturbing.

Asked By Kevin Dickson, MSME | Sep 12 14
11 Answers

I need help choosing the correct minisplit and heat pump for my studio

I have two proposals to install a single unit mini-split with an outdoor condenser for my studio building. The building has a 24 x 32' foot print. The walls are 10' high, with a cathedral ceiling that is 16' high at the ridge. Walls are 2 x 6 (at least) with fiberglass batts. Roof rafters are 2 x10" (I think) with fiberglass batts between, and then either 1 or 2" rigid foam insulation skimming it (under the sheetrock). Building is tight. Floor also has fiberglass and rigid foam board between the 2 x 12" joists.

Asked By DANIEL GOTTSEGEN | Sep 10 14
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
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