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5 Answers

Minisplit vs Wall heater for raised ranch

Thanks to everyone who contributes to the blogs here, I have been reading everything on the site for years.

I have a friend with a small raised ranch which is heated with baseboard electric heat (!) and I'm helping him move toward something else. My suggestion is a minsplit with the head located in the living room which is fairly open to the dining area and kitchen. By locating it fairly centrally the head will also provide some heat to the three bedrooms and bath. The electric baseboards will supplement that - they are used to cold BRs (out of necessity).

Asked By Albany Landlord | Jan 22 18
15 Answers

What should I replace my heating and cooling system with?

Hi all,

I'm looking for advice on the 'best' solution to my heating and cooling (and hot water)

- Zone 5b
- Loads from coolcalc and manual D/J
Heating loads
- Main house: 28k to 36k, 900 cfm
- Sunroom addition (can be closed off): 8k, 150 cfm unducted not planning to directly heat (current situation)
- Office addition 5k/3k, 180 cfm. Unducted, can probably be heated via staircase.

Cooling:
- Main house cooling load: 24k to 36k, 1200 cfm
- Sunroom addition: 8k, 450 cfm unducted not planning to directly heat (current situation)

Asked By Jill D | Jan 17 18
1 Answer

Mini-split zone and placement recommendations

Floor plans attached with heat loads and windows called out. What would you recommend for zones and placement?

Thank you

Asked By user-6925805 | Jan 22 18
11 Answers

I’m interested in disconnecting from the grid

Our house is tight. One of my big winter loads is the clothes dryer. I am getting questionable reviews on heat pump dryers. Should we just “freeze dry “ laundry on the porch. Are there any options?

We had poor reliability with two different horizontal axis washers and now have a Maytag. It spins but not like a horiz. axis.

Thanks.
Steve in Wellsboro

Asked By Steven McCarthy | Jan 18 18
10 Answers

Review placement and sizing of mini-splits

I have been reviewing the submittal sheets along with what feels like endless reading on this site. Through all the reading and studying I feel like I have a decent sizing and placement locations figured out but would like second opinion.

Front door faces NE and I'm in CZ 4A, 24149. The fireplace is a vented gas fireplace that is vented out the adjacent covered porch roof, no chimney. Patio doors where changed to single doors.

Design temps: 17/89. Indoor temp year round will be set at 72.

Asked By Kevin Lucas | Jan 14 18
6 Answers

Are there benefits or serious drawbacks to using a variable speed air handler with a single speed compressor?

We're restoring a 19th century house in very humid Gulf Coastal climate, similar to New Orleans. We askled HVAC company for variable speed heat pump, and got a quote on a variable speed air handler matched (by the manufacturer) to what appears to be a single stage 14 seer outside unit. I appreciate that there are small benefits to variable speed for heating loads, but don't give a flip about that in our climate.

Asked By user-6970120 | Jan 18 18
8 Answers

Heat Pump +/- gas furnace

I am building in the mountains of western NC, Zone 4. The bid calls for a Trane 17 SEER, 9.6 HSPF two-stage, variable speed heat pump with a gas furnace backup.The house will be about 4000sf on 2 floors over a crawl, very well insulated, tight, triple pain windows with 10kW of solar. Do you think this is the correct choice for HVAC or is there something better(always considering cost, of course)? Is the gas furnace backup needed?

Asked By Kevin Spellman | Jan 17 18
8 Answers

Should we actively condition our unfinished basement?

We’re in SW Virginia, building a 2 story, 1900 sq ft home with a full basement. 2 inches of XPS foam under the slab, and 2 inches of polyiso on the interior of basement walls. Heat pump/forced air and woodstove will heat upper floors. Future plans include doubling the thickness of polyiso all around in the basement. Was also thinking that if we had cold floors on the first floor, I could add some insulation under the floor.

Asked By William Costello | Jan 17 18
2 Answers

Power vent water heater is backfeeding cold air

Hi guys, We here in Michigan just got over a single digit 11 day cold spell. This is where you really can test your basement for cold air leaks. Speaking of that, I waked by my water tank and was pretty much blown back by a wave of cold air. So when the fan kicks on it pulls air from the basement to vent the gas out the rim joist through 2" pvc tube. Ok, that's great. Now when the fan is not blowing the pvc is just letting the cold outside air to backfeed right through the fan intake into the basement.

Asked By Mid Michigan | Jan 10 18
5 Answers

Flow Rated Fans - How Do They Regulate?

Bathroom-style fans like Panasonic's WhisperGreen units regulate their speed to ensure consistent airflow as restriction varies downstream. Does anyone know how this works exactly? I'm assuming it would use a pressure sensor on the exit side of the fan and have programmed speed values for differing levels of restriction, but that's just me guessing.

Asked By Lance Peters | Jan 8 18
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