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3 Answers

ERV odour?

I've read of issues of some ERV units having a "plasticky" stink, as discussed on some austrian and german forums, which affects certain batches of enthalpy heat exchangers made by paul, and used by zehnder and helios among others.

But that aside, how would an ERV cope with removing odours made by regular but moderte cooking?

For example, we stir fry vegetables and grill meat maybe twice a week rest of the time it's just pasta or eggs or some soups.

Equivalent of climate zone 4 (~philladelphia), 3 people in a new 2200sqft house.

Asked By davor radman | Jun 28 17
2 Answers

Non-electric Fresh Air vents

I am considering using the Lunos type of ventilation fans which seem to require electricity all the time in order to work. Has anyone used these non-electric ventilation devices?

This is for an off grid cabin run on PV panels.

Asked By Scott Wilson | Jun 27 17
13 Answers

Drainwater heat recovery questions

Hello, I've been reading some things on drainwater heat recovery and came upon this article:

In it, Lyndon Than says, "Leave at least a 12-inch run of straight drain pipe above the exchanger to smooth out the flow."

How critical is that? I don't have.much room to work with -- about 36" in total. I could likely get a 30" unit in that space, but if the 12" above is necessary, it wouldn't be worth the trouble.

Asked By Calum Wilde | Jun 26 17
8 Answers

Which ductless minisplit?

Zone 4 climate - 735 sqft - R25 walls - R40 roof - R5 windows - very tight ICF home - glazing is minimal with a low SHGC

A Manual J was done and it showed a 1 ton unit would heat/cool the home. I'm undecided if I should bump up to a 1.5 ton unit? Here are my options:

A - DuctlessAire Mini-Split - 1.5 ton - 21.0 SEER - $1,400
B - DuctlessAire Mini-Split - 1 ton - 21.5 SEER $1,060

Is it worth the extra $340 to up-size to the 1.5 ton unit?

Asked By Peter L | Jun 22 17
6 Answers

Considering ERV pre-heating options (maybe cooling too)

Hello from a long-time lurker but first-time poster!

It's hard to express how helpful and inspiring this website is to a non-professional like myself. I'm particularly taken by the generosity of spirit shown by all who contribute thoughts, ideas, and experience with such passion. It seems that everyone wants to do their part to help heal our hurting planet--buildings are a huge part. Thank you, thank you.

Okay...end of speech. Some details about our build plans.

Asked By Richard Hoenich | Jun 24 17
3 Answers

Are Blueridge mini-splits any good?

Hi All,
Does anyone have any experience with Blueridge mini-splits? They seem to be the house brand of Alpine Home Air. Any idea who makes them? Are they any good?

Asked By Ben Rush | Jun 20 17
4 Answers

Add on demand to boiler system

We have a baseboard hot water boiler that is also used to heat our DHW(built in 1988). Seems we have larger than average gas bills even in summer. I have noticed that the boiler comes on even after 1 shower.
I am not sure if the temp set points are too low, boiler needs inspection, or to eliminate the side arm from boiler to DHW( Then add an on demand water heater). Bill over $100 mth seem very high for 2 people.

Asked By Bill Skaff | Jun 15 17
1 Answer

Measuring vent area for whole house fan

Considering installing a 6000 CFM whole house fan in our 3200 square foot house. The fan we are considering is the QuietCool QC-CL-6400, and the manufacturer recommends 8 square feet of vent area in the attic.

Two questions:

1. What vents can I count towards the required vent area? I would think, with the attic pressurized, any "official" opening (gable vents, ridge vent, soffit vents, etc.) could be counted. Is this true?

Asked By Matt Culik | Jun 13 17
20 Answers

Electric tankless hot water

My name is John, and I'm an instructor at Madison Area Tech College in Madison Wi, in the Construction and Remodeling Program. We train or students in a 1 year diploma program how to be wood frame carpenters. We build super high efficient tiny homes with the students, that we sell. We incorporate lots of things talked about on this site. One thing we are trying to figure out: How to efficiently heat water without taking up too much space.

Asked By John Stephany | Feb 7 17
1 Answer

What is the average annual cost to operate a residential mechanical ventilation system in a typical 1800 sq. ft. home?

For low-income energy efficiency programs in CA, we are trying to estimate the average cost/year to operate a residential whole-dwelling mechanical ventilation system.
• For our programs, the assumed electric rate is $0.17 / kWh.
• I am seeking research information that will help us estimate the average annual cost to operate a typical residential mechanical ventilation system.
• If you can help me, or can refer me to someone who might be able to, please do!
Andre Grieco

Asked By CageyAG | Jun 8 17
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