Jonathan,
There are several passive houses in Portland with range ventilation hoods which do not exhaust to outdoors and rely on the hoods to filter the air and the HRV ventilation system to exhaust it.
I've used this since January 2010, and even with our gas range/oven, we've had no problem with city approval or IAQ.
We have a sensitive CO monitor, and the only time it detects CO is when we use our gas oven. That's rare, and we simply operate our HRV at its measured maximum 187 cfm exhaust (with 63 cfm measured exhaust from the kitchen exhaust). We have a CO2 monitor nearby, and only the oven will push us over 1,000 ppm. We're saving for a conduction stove top and electric oven.
Our commissioning test results are attached for our ZehnderAmerica CA350.
Our kitchen exhaust is shy of 100 cfm, but it is sufficient as other air passes through the kitchen on the way to the nearby bathroom (with 34 cfm measured exhaust). Also, I believe most people take the position that continuous kitchen exhaust allows a lower intermittent exhaust rate.
As you'll note from the attached report, when we want exhaust primarily from bathrooms (e.g, for peak moisture loads like my teenager's showers), we activate (from switches in any of the 3 bathrooms) a damper that increases the exhaust rate in all 3 bathrooms.
We find this is essential to quickly remove most of the moisture from the bathroom when a person takes a long shower. That reduces the exhaust from the kitchen, but we get nearly 60 cfm exhaust from each bathroom.
This has not caused problems with kitchen ventilation. Probably because the downstairs bathroom is pulls part of its exhaust air through the kitchen. Also, most bathroom moisture loads are morning showers and kitchen ventilation needs are highest in the evening. At any rate, we've had no problems.
Recently, PDX Living LLC and Green Hammer both separately obtained written approval from the City of Portland for substituting mechanical (HRV) exhaust system for range hoods vented to the outdoors. Both relied on the fact that the kitchen exhaust was continuous.
action=entry&appeal_id=10080
When we retrofit our home to be a passive house we moved our gas-fired clothes dryer to our garage. However, since then I have reviewed condensing and heat pump dryers.
Years ago, we elected to wait for a heat pump dryer even thought it would have less waste heat than a condensing dryer. Another factor in my decision what learning that some condensing dryers use potable water to condense the moisture in the dryer air.
I understand that heat pump clothes dryers may be available this year in the US. However, they are complicated mechanically, and we hope we've found a solution for indoor winter clothes drying that has the virtue of simplicity and synergy.
Especially as our complex, technological living arrangement cause long-term damage to the Earth, I'm persuaded that our solutions must be as simple as possible. I am indebted to Katrin Klingenberg for teaching that simplicity must always be a guiding design principle.
For years, we've hung damp clothes in the bathroom nearest our clothes washer. Our washer has a high-speed spin, so they are not as wet as clothes from old washers. They dry quickly on the portable drying racks we leave in the shower stall (another way that continuous HRV ventilation helps). We find that clothes dry easily overnight. Then if you prefer your clothes softer, you can give them a short run in the dryer with a damp towel.
However, there are lots of things we don't want to hang up in our bathroom. So, we recently purchased an Asko clothes drying cabinet which sits right next to our clothes washer (where our dryer was before we exiled it to the garage).
It is a metal cabinet roughly 2 feet square and 6 feet tall. It includes a 34-watt fan, 1,200-watt resistance heater, and 52 feet of clothes rods. It is rated to dry a full load in 1.5 hours (with heat) or about 8 hours (without heat).
Again, a mechanical, balanced whole-house ventilation system makes this possible since we can exhaust the moist air from the cabinet directly into the exhaust ducts and exhaust the moisture outside the house. With heat recovery, we'll not only get dry clothes but heat our house with the 1,200-watt heater.
Our utility's source energy is 40% coal, and I'm working to change that. However, we pay a premium to purchase 100% wind power so that at least we nudging our utility to a cleaner source. And there is almost always plenty of wind at least somewhere in Oregon all winter.
We haven't used the cabinet yet, but hope to soon. Hope to have it operating by month's end.
Good luck!
Tad