I see that new houses (in Ontario for example) are built with HRVs, no bathroom fans, and recirculating charcoal filter for the range hood. This way, next to no heat is simply lost outside the house.
I have installed an HRV but I'm not sure if I should go ahead and remove the bathroom fans. I could install 20 minute timers to kick the HRV into high speed during showers. I'm worried that the one-way flap of the bathroom fans won't prevent outside air to be simply suctionned through the HRV, reducing the efficiency.
I'd rather keep the range hood ducted outside, but then again, recirculating would be more energy efficient and prevent negative pressure.
Thoughts? Preferences? Ideas?
You may want to consider ducting the HRV to the baths for exhaust air ,not the range of course.Then add a switch to energize the HRv from each bath.
Take a look here http://www.fantech.net they have "central " bath exhausts ,with grilles etc..Just imagine your HRV as the fan/blower.
Design is critical for the ducting to each bath,you'll need a Pro for that part.
Typically HRVs draw in exhaust from areas that typically produce high humidity, such as washrooms, the kitchen, perhaps a laundry area. They give good IAQ, and keep winter time RH down to a point that will avoid window condensation problems.
An HRV with multiple exhaust intakes can end up being a low CFM per intake. The flow rate into each intake could work out to be perhaps 30 CFM.
Sometimes there is a desire for a quick removal of odours so you could keep the bathroom fans. I would also keep the range hood ducted outside, especically if it is a gas range.
When these exhaust fans operate they do create a negative pressure inside your home. Maybe check with hrai.org and get a certified ventilation contractor to come in, balance your HRV for you and check combustion air issues.
The way we build has a greater impact on our comfort, energy consumption and IAQ than any HVAC system we install.
The main reason kitchen range hoods are vented inside the home is cost. It's cheaper for the builder to not duct to the outside, so they don't. Energy savings are IMHO just an excuse - the filters are expensive and they don't work nearly as well as venting to the outside. I wouldn't want to run smoky, greasy range hood exhaust through an ERV, either.
I would say just keep your fans too. I had an HRV installed (in Ontario) but after I moved in. I kept (and still use) the bath fans. With the fans and HRV you can "clear the room" in no time flat!