HRV Ducting / Fresh Air Termination Points

Oliver,

For an exact answer, we would need to have the full house plans, but the contractor's suggestion sounds reasonable. You local building code has also an effect on its installation.

The basic principle is to remove the humid air from its source (bathroom, kitchen) and inject fresh, dry (and cold) air back in the house. The problem is that this can cause a cold draft if it is injected into a living space.

If you had a central ventilation system, it could be used to distribute the fresh air. You probably don't have this. The closets are the next best places as they will allow the air to pre-heat and diffuse slowly. Don't use the wife's closet as she will not appreciate the cold clothes in the morning... I suggest to use a few closets to distribute the air. Your teenage son's closet (and yours) are a good choice to dilute the testosterone floating in his room especially if you plays sports or work hard...

Some units use a pre-heater to prevent the draft effect. Then the outlet location is not important.

You are making a good decision to add ventilation in a house that is too air tight. The energy bill will increase a little but the health costs will go down. I have a similar system ans prefer spending money on electricity rather than on medication...

Keep the humidity setting so that you have little condensation in the windows. Going below 40% RH is only acceptable in the coldest days (<-25C). Your HRV book will have some useful info on this.

Finally, I placed mine on a 24h timer. I run it during the night in the summer and during the day in the winter to minimize the cooling/heating costs. Some newer HVR do this automatically. I also placed the stale air discharge in the garage to recover the wasted heat. I was warned not to do this as it would increase the humidity and rust the cars but the humidity produces is negligible compared to bringing the car covered with show in the garage. I haven't seen any rust on the iron bar I placed near the outlet to monitor the increase rusting claim. Had this running since 2001.