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0 Answers

Recommendations for a small HRV

Hi everyone
I'm looking to buy an HRV for our small (1000 sqft) ranch home.

I already installed all the dedicated ductwork last year and had been using a home-made HRV that worked very well, but I don't have the time to keep tinkering with it to get it to work just right. The cabinet was made of plywood and I kept having problems with the air streams crossing and causing condensation and mold in the cabinet.
Anyway as a result I'm going to hook up a new HRV to my ductwork.

I'd like a small unit - I will be installing it in a closet
Quiet would be good
Also with ports on top

Asked By Carlo Giombi | Oct 12 15
5 Answers

Gree Mini-split heat pumps

I'm hoping Dana will weigh in on this question given his expertise with specifying and analyzing mini-split heat pumps.

There are some new heat pumps on the market from Gree that appear to approach the performance of the best units from Mitsubishi and Fujitsu. It appears to me that the cooling efficiency is right up there with Mitsubishi and Fujitsu, though the heating efficiency isn't as good. They do however specify heating capacity down to -20 degrees F.

Asked By Joshua van Tol | Oct 9 15
11 Answers

Moving a gas water heater into the envelope of the home...or switch to electric?

I just acquired a early 90's home and it turns out we can't get our minivans into the garage! On one side we have the HVAC equipment and on the other the water heater (both are gas). The HVAC I think we can relocate to an area of the bonus room directly over the garage so there will be minimal adjustment needed to the duct work. The logical place to relocate the water heater will be just inside on the same wall it is now which is currently a laundry room. I have never had a house with gas units inside the envelope of the home. So....

Asked By Andrew Bennett | Oct 9 15
3 Answers

Fantech MUAS

Is anyone familiar with this product/strategy? We are working on a custom home in Louisiana and are interested in utilizing it. We discussed a make-up air for the range hood when the fireplace damper is open, and we're thinking that this might be a good solution. I'd appreciate your feedback. Thanks!

Asked By Heather Gayle Holdridge | Oct 9 15
14 Answers

HVAC selection help

My new house is under construction and I need to finalize my HVAC system soon. Some details:

Zone 4, 3800 sq feet (About 1900 first floor, 1550 second floor, 350 room over the garage), crawl space (conditioned), open web floor trusses for second floor.

I had the manual J load calc reviewed by an engineer and have sent it back for some corrections (there is better insulation than is shown and better air sealing, and a couple other things which will lower the load. He didn't add the ventilation load though, which will raise it), but as it stands right now:

Asked By Michael Geoghegan | Oct 7 15
8 Answers

Is makeup air needed for a propane boiler?

We are building a 2200 s.f. house with closed cell insulation and heated with propane radiant heat. The plumber says I don't need makeup air. He says the HRV will handle it and I just need to put a louvered door in the mechanical room. Please advise. Thanks!

Asked By Peter | Sep 28 15
2 Answers

Air sealing & insulating above Mitsubishi ceiling cassettes

Found this response in a related question but wonder if you can illustrate if anyone has an elegant solution for keeping the ceiling cassettes and their awkwardly placed pipes sealed inside the envelope and still making it possible to service from above should it be necessary.

Asked By Mary Quigley | Oct 7 15
7 Answers

Solar hot water system with oil heat, one hot water tank or two?


I'm wondering if someone could help me. I am very new to the site so I apologize if I have missed the answer to this question in the archives.

We have a solar hot water system (geothermal, installed 2007, has already paid for itself - I have read the articles on photovoltaic systems) in a house that has oil heat. [Editor's note: Audrey later clarified these remarks by noting that the reference to a "geothermal" system is erroneous; the intended reference was to a solar thermal domestic hot water system.]

Asked By Audrey | Oct 5 15
1 Answer

Ductless heat pumps and conditioned crawl space

Any suggestions for using the two together? I'm intrigued by the efficiency of the DHP's, but don't know how I can get some of the conditioned air into the crawl space without auxiliary fans or such. Thank you for your help.

Asked By Philip Joyal | Oct 5 15
10 Answers

How to release stored heat in floor's thermal mass

Years in the planning, five months in building, we are now home at last in our 1,100 sq passive home at 46 degrees North in North Central Minnesota.

Fujitsu Halcyon mini split heating and cooling.Heat load is around 26K BTU

Q 1. Am I correct assuming that I have to set the the two mini splits' thermostats at a night time temp that is lower than indoor temp before the concerete floor's thermal mass will release its heat?

Last night I set mini splits at 66 degrees -- guessing that that setting would be cooler than floor.

Asked By Randy Bunney | Oct 2 15
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