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14 Answers

Geothermal vs. air-source heat pump

I have researching and getting quotes on hvac for a while now.. It is getting to crunch time.
Well insulated, tight house.

All three quotes include:
3 units, 3 air handlers, each zoned 3 times. Rigid Trunks and short flex runs.

option A. Carrier 18seer 25vna08... 5 stage. ( I don't like the potential harmonics problems of their greenspeed)

option B. Lennox x25 top of their line variable.

option c. Waterfurnace 7 series geothermal units. horizontally drilled ground loop.

Asked By Dean Sandbo | Jun 22 16
14 Answers

Options for replacing 2-cycle gas weedwhacker / string trimmer?

I recently replaced my gas-powered push lawnmower with a manual reel mower (Fiskars Staysharp Max Reel Mower, 18-Inch) for maintaining the grass on our small (7,500 sq ft) lot.

Asked By Robert Hallenbeck | Jun 26 16
2 Answers

Lowe's ThermaTru Doors

Looking to get a reasonably priced but energy efficient entry door. Lowe's sells fiberglass TheraTru doors with polyurethane that initially seem to be around U-Value of .21 which seems pretty good for a door. They also have a triple locking mechanism.

Any pros, cons or feedback on these doors?

Asked By Peter L | Jun 27 16
0 Answers

Zone 1 dual zone home addition HVAC strategy

I'm building a 1,700 sq foot single story addition to my home in Houston, TX. 1,000 sq foot are a woodworking shop, 700 sq feet are living space. Living space is multi-room, think small apartment (kitchen/den, bedroom, bathroom, closet). Shop is one big room with a separate mechanical room. My current HVAC system won't handle the 700 sq feet of living space, which is also on the opposite side of the shop (maybe 100' from the current hot-attic system).

Current house is traditional stick frame, brick veneer with batt insulation and blown-in in attic. Gas available for heat.

Asked By Mark McFarlane | Jun 27 16
4 Answers

dehumidifier needed in tight house?

I've read several times that it's common for tight, well-insulated homes to need supplemental dehumidification, as the AC doesn't run enough to dehumidify the home.
As a person who is especially sensitive to humidity, I'm very interested in this.
I wonder if an equal level of comfort can be achieved more economically with a higher temp. set point but lower humidity. (In my case, Chicago area- warm and humid in the summer).

Asked By Ben Rush | Jun 27 16
15 Answers

R-values of ceiling and walls

Zone 5a (on the border of zone 4)
Existing uninsulated concrete slab.
No basement. 2x4 frame.
A bunch of newbie questions.

http://www.homepower.com/insulation-zones
Why is the insulation recommendation for an attic so much higher than for an cathedral ceiling?
Both are the shell of the building but the attic has an ceiling under it that at least adds some insulation value. I would expect the recommendations to be closer or even reversed.

Many sites stress the importance of a high R-value to save energy.

Asked By Tony Tibbar | Jun 3 16
0 Answers

2 layers of insualtion or 1?

Hi

We are installing 2" of Hi-load xps ridgid foam insulation under a heated slab in zone 4a and we have the option of doing 1 layer of 2" insulation or 2 layers of 1" insulation. i'm wondering if there is an advantage to overlapping the seams or if it's inconsequential at the end of the day. we will be taping the seams.

thanks,

bigern

Asked By Big Ern | Jun 27 16
28 Answers

Direct vent vs. power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
8 Answers

Insulation/ conductivity math help, please

I recently read one of Martin's posts about (so-called) radiant floor heating.
It was exactly what I needed. The dream of a toasty-warm floor under bare feet is only a dream- unless the boiler runs all the time- either to keep up with a poorly insulated and/or drafty house- or if a well-insulated, tight house is overheated.
Instead, I'll opt for mini-splits.

Asked By Ben Rush | Jun 25 16
8 Answers

Insulation distribution with a low ceiling; efficiency vs. comfort

Context: a 14' x 7' x 6'8 tiny house built on a step-van chassis. Heated by wood and propane. Designed for Zones 4-7. Primary occupant 5'10 or so. Insulation is reclaimed polyiso, mostly 4" with a few 2".

Asked By Geva edhrven | Jun 26 16
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