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3 Answers

Geothermal and SDHV in new ICF home

We are in the process of building a new home in CZ5. It is an ICF construction from basement foundation to gable.

I am intending to use a SDHV system for forced air and heating in conjunction with a closed loop ground source heat pump.

What I am trying to understand is the impact to efficiency caused by my desire for SDHV on the heat pump options side of life.

Asked By Esteban Carlos | Feb 4 16
5 Answers

Wall assembly

I am not sure this is the correct place to ask this question but here it is. I am building a new home in NW Wyoming. I will have a sealed and conditions crawlspace under half the house. I have installed a radon system. The crawlspace has a poly sheet under a rat slab. The hvac is located in the crawlspace. Would it be a good idea to have the returns for the bedrooms and baths to vent into this crawlspace. It will also be insulated on the walls internally with rigid foam.

Asked By Charles Cloud | Jan 29 16
0 Answers

Chinese Split Heat Pump Water Heaters

Sanden is getting a lot of attention due to their Eco-Cute split heat pump water heater using CO2 refrigerant.

In China though there seem to be many manufacturers making split heat pump water heaters using Japanese compressors (albeit with more common refrigerants). On or do a search for "heat pump water heater" or "evi heat pump" or "twin rotary heat pump" and the options seem to be endless.

Asked By Osman Anwer | Feb 3 16
2 Answers

they didnt completely hook the cold air return on my furnace is that ok what could happen

can just using indoor instead of fresh outside air cause any problems

Asked By Roger Blankenship II | Feb 1 16
3 Answers

Water Heater Morass

Hi all. I'm in the midst of a seemingly one-step forward one-step back basement renovation. On the "step-back" side, our water heater is nearing the end of it's life. From what a can glean from the label/internet, It's a ~10 year old AO Smith, .54, 60,000BTU, 48 gallon tank, with a stated 90-gallon 1st hour rating and 61 gallon recovery rate. We're a family of four (with a 4 and 2 year old) in a 2 bath (probably soon to be 3) house in mid-Ohio with a detached garage.

Asked By Matt Bierlein | Jan 30 16
2 Answers

Passive emergency encapsulated crawl space drain

Hi. I'm finishing the design of my encapsulated crawl space project for this summer. The soil gets visibly damp at times due to a natural spring that moistens my whole hillside once a year but no standing water or droplets ever form. And the soil is sandy and high clay I think.

I don't think I need a sump pump pit installed and neither does a couple of contractors I asked.

But if a pipe ever leaked (either the supply from the well, or after my cistern/boost pump piping) I'd want a relief so my CS doesn't become a mountain pool.

Asked By Andy Nels | Jan 30 16
7 Answers

Evaluating HVAC schemes for retrofit?

I've been planning a major retrofit to our 100 year old farmhouse and its coming down to crunch time. No surprise here, but the HVAC system has been the most challenging. I'm hoping that the astute staff and readers of GBA can offer fresh critiques and/or alternatives to the proposed scheme.

Asked By Edward Odgers | Jan 26 16
6 Answers

Duct sizing for Fujitsu 9RLSFCD concealed duct unit

Hi All,

I am planning to install Fujitsu 9RLFCD concealed duct unit and can’t figure out way what size duct should I use and how to determine how many CFM does each room need. I have a heat loss done for each bedroom.

The plan is to put unit in the lower level aka basement (it’s split entry home) and run the duct work to the 3 bedrooms thru the floor. All three bedrooms are next to each other and would not require more than 4-6ft of ducts to each bedroom.

Asked By Alex Frost | Jan 28 16
2 Answers

Can Panasonic ERVs be on programmable timers?

I am installing a couple of the Panasonic spot ERVs and the directions clearly state not to put them on a solid state controller. The directions state that the harmonics from a solid state controller can effect the motor and make it run noisily and even the possibility of fire. This would limit you from using any programmable timer that I know of. I hear of people putting these on programmable timers thou. Am I missing something? Has anyone had any experience with this? Thanks ahead of time.

Asked By Kail Zuschlag | Jan 27 16
42 Answers

Seeking an air-to-water heat pump

I'm looking for an air-to-water heat pump and feedback from those who've used them. We have a LEED for Homes project in Victoria, BC, perfect climate for heat pump, affordability of project prohibits groundsource for 36Kbtu heat loss of 1800 ft2 home and for optimal comfort, low temp/efficiency, to avoid ducting we're selected hydronic in-slab for heating distribution thus standard air-to-air heat pump is a no-go.

Asked By Allison Ashcroft | Jul 28 09
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