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6 Answers

Mitsubishi sizing

I've built a SIP Panel house, 6" R24 walls and 10" R40 roof, Low E windows .31 on the sliders and .29 on the standard 3x5 windows. Floors will be packed with cellulose between my to be finished basement at a later date. I'm currently

Asked By Colt Freeman | Oct 5 16
2 Answers

Wall-mounted bath fan in an uninsulated brick wall

Hi, I live in a 100 year-old row home in Montreal, (where it can easily go down to -20 in the winter). The walls are double brick with no insulation, luckily most walls are abutted by an adjoining home. There are a few exposed walls in bump-outs though. One of those walls is our master bathroom, which has no fan. I want to install one.

Asked By Sean Lewkiw | Oct 7 16
13 Answers

Hydronic in-slab heat for basement

I'm remodeling a 1700 sq ft basement under a single story 1959 ranch house in Nashville, TN (zone 4). The slab was so poorly done that we decided to cut it up and re-pour. This will give us 4-5 extra inches of basement headroom, around 7'11".

I'm planning to install hydronic in-slab heat for the entire basement. There is already an HVAC system for the main floor and the duct work is in the basement. I think a few registers will handle cooling in the basement in the summer. I assume we can always close off the vents in the basement in the summer if it gets too cool.

Asked By Beau Bristow | Oct 2 16
3 Answers

Heat pumps and traditional heating

We are about to install a Fujitsu minisplit heat pump for our cooling and heating needs in our 100 year old 2000 sq foot row-home in Montreal Canada, (zone 8 million). We currently have electric hot water radiator heating.

I am curious how I manage to keep the two units from "fighting" each other over who gets to heat the house. I know that when the depths of winter arrive, the heat pump alone will not be able to heat our home.

Is it simply a matter of setting the thermostat for our main heating system a degree lower than the minisplit?

Asked By Sean Lewkiw | Sep 30 16
9 Answers

Minisplit Design for Whole House

Hello, first of all thank you GBA for all of your articles, I have read many and found them to very helpful and interesting.

I am renovating my house (in Tampa, FL) and installing a new AC system, I will be installing minisplits most likely DIY, but will also talk with installers. I want to see what GBA users recommendations are for how I should design my system.

Asked By Jimmy Black | Sep 29 16
4 Answers

Can a ductless mini-split heat pump be installed for a walk-in cooler?

I have a contractor that installed a Fujitsu AOU12RLS3/ASU12RLS3 in a walk-in cooler for a restaurant. They claimed that it was more efficient than a traditional cooling system. Is this an acceptable installation for this system?

Asked By Kristin McAlpine | Sep 29 16
6 Answers

Please help me pick the best option for HVAC replacement

We moved into this 20 year old house here in Nashville, TN in June and have been doing various projects to bring the home up to and above current building best practices. We have put open cell foam in the attic (average ~8 inches with rafters covered) and have encapsulated and foamed the crawl with 1.5 in of closed cell and 12 mil vapor barrier. We replaced the upstairs HVAC with a new 5 ton Trane xr17 and S9v2 furnace.

Asked By John Sexton | Sep 8 16
3 Answers

Do I have an issue?

The weather is my part of Zone 3 is still pretty hot (90s during the day with a cooling trend into the upper 80s). I noticed that my two year old air-source heat pump is struggling a bit to keep things comfortable. The thermostat upstairs is set for 77 degrees but the temperature is hovering around 81.

I also observed some wetness under my outdoor unit as well as some similar signs of water in the pan under the air handler. What do you guys think? Am I low on refrigerant? What might cause that?

Asked By Steve Knapp CZ 3A Georgia | Sep 26 16
3 Answers

Is HPWH reliability still an issue?

I'm seeing a lot of negative feedback on the reliability of heat-pump water heaters. Are they much more prone to problems than straight resistance heaters? If you had to choose a 50-gallon domestic model, what would you choose?

Asked By Charles Campbell | Sep 23 16
2 Answers

Temperature adjustment / offset on Mitsubishi minisplit

I installed my MSZ-FH12NA two months ago and the unit is performing very well and I am not experiencing the short-cycling issue that others have, but the unit seems to consistently cool (haven't used heating mode yet) past the set temp on the remote by 4-5 degrees. (If I want it to cool to 70, I have to set the remote at ~74.) Does anyone know if there is a way to offset/adjust the remote control temperature to accurately reflect the actual room temperature?

Asked By Adam Emter | Sep 22 16
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