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5 Answers

Split system location

If I am going to install a mini-split in a very small, well sealed, well-insulated new home that will need airconditioning rarely (maybe never) but heat more often, does it make sense to install the interior unit at floor level instead of ceiling level? Is there generally an option offered by mfgr of low or high mounted units?

Asked By A Lange | Nov 24 15
13 Answers

Ideal load for a multispeed inverter-driven GSHP?

In a planned "Pretty Good House" in Mixed Humid, Northern Climate Zone 4, I intend to use a 45 EER Ground Source Heat Pump with 3 inverters (loop pump, compressor, and fan) with a Cooling Capacity range from 9,000 - 24,000 Btu. I wish to have the lowest Peak Cooling Load, that utilizes the equipment most efficiently, while providing dehumidification and keeps short cycling to a minimum. Approximately what sould that theoretical Peak Cooling load be ?

Asked By Ted | Nov 19 15
8 Answers

ERV or HRV that scrubs the incoming air?

Hello all, I'm planning a new home and need some help on a ventilation issue. A couple of my neighbors burn a lot of wood in the winter, so much that you smell like a BBQ pit after a few minutes outdoors sometimes. Is there any ventilation system on the market that would scrub incoming air--activated carbon maybe? Or can anyone think of way to alter ventilation ducts on a typical ERV or HRV to do so that is safe for the systems and for me?

Asked By Antonio Oliver | Oct 9 14
2 Answers

Using well water for air conditioning

A random thought occurred to me while I was thinking about the Chiltrix system. For air conditioning, water at about 55 degrees would be circulated through the fan coils. That is about the temperature of the water coming out of my well all year. If the system was only used for air conditioning, could the well be the source of the cold water as opposed to running a compressor? I don't see a problem with this idea, but I expect that if it was simple at least some people would be doing it. Am I missing a major flaw?

Asked By Reid Baldwin | Nov 21 15
3 Answers

Desuperheater water heater

I always understood that if you had a GSHP with a desuperheater, that your water heater should be an electric tank type. A client we are designing a home for would prefer a gas tank over electric, and our MEP engineer has not suggested that this would create any issues. Please advise.

Asked By Heather Gayle Holdridge | Nov 19 15
3 Answers

Zoned HVAC and dampers — Opinions?

Townhome has a zoned (3-levels) HVAC system. This system contains four trunk lines off the supply plenum one of which contains a weighted (manually adjusted) damper that was originally routed back into the supply plenum. This weighted damper is designed to provide bleed off air when less than 3 zones are in use.

You would adjust the damper by so that is operated as follows:

3-zones in use (damper is basically closed)
2-zones in use (damper partially open)
1-zone in use (damps is slightly more open vs 2 zones in use).


Asked By Chris M | Nov 18 15
7 Answers

Need a stealthy ERV installation

Hi, I own a 1450 SQFT home that has been spray foamed throughout (walls, attic, etc.) and has decent triple pane windows, but minimal to no passive solar due to orientation and surroundings. Although the home is 75 years old, a blower-door test revealed its tighter than most new builds, so I need a ERV as soon as possible. I chose an ERV over an HRV due to the humid summers and long dry winters here in MN. The home has a 96% efficiency gas furnace and central AC. The furnace has a multispeed fan.

Asked By Ryan Griffin | Oct 23 15
5 Answers

Control a heat pump with a wall thermostat?

I have recently installed an airsource heat pump in my vacation house in central Vermont. It works great, and mostly replaces the electric baseboard heating.

My concern is that the unit can only be controlled by a hand held remote, and only goes down to 60 degrees. We normally leave the house at 45 when we are away. It seems to me I am wasting a lot of energy now, perhaps using even more than the baseboards at 45.

Asked By Philip | Nov 17 15
30 Answers

HRV vs. whole-house dehumidifier — Need help choosing

Hello, I have a 1700 sq ft house located about an hour North of Albany, NY. The house was built in 1998, and I just purchased it last year, it is fairly tight, but nothing exotic. It has 2x6 walls with fiberglass insulation,R-60 in the ceiling, double pane vinyl windows, and vinyl siding. The house has a few year old high efficiency forced air propane furnace and no AC.

Asked By Chris Yarsevich | Oct 26 15
2 Answers

3-story apartment foundations?

Tips for this? Requirements?

Asked By Jose Tribaco | Nov 15 15
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