What are the HRV or ERV options for 40-yr 2-storey 2000 sq ft home?
The local ventilation consultants wish to install a second ducting system, in addition to the returns and ducts for a electric-wood forced hot air system
For a house of its age and depreciation, and our likely ten additional years ownership, the investment of $4000 is too high
The street wise contractors say, just open a window
In Aug 2019 we installed a mini-split which heats the upstairs 800 sq feet until outside temps fall to zero degrees C, after which the forced hot air must supplement it
Have any new options appeared on the market that I can consider?
There is an ‘aftermarket’ solution for installing HRV and ERVs during renovations, though I can’t guarantee how much it will cost.
First though, you need to realize that rely on opening a window for fresh air will in the long run be an expensive solution to bring fresh air into a home, and when you aim to sell it you would likely benefit by having a ventilation solution beyond just 'open window'. I can't guarantee this will fit your budget but have a look here at ductless wall insert ERVs and HRVs can be a more simple ventilation solution for older homes than gutting it to run ducts.
Ductless wall insert ERVs for renovations and new home builds
This system works in pairs, where each unit has a ceramic core and its own fan. One blows in while the other blows out, and the change direction every 70 seconds, this way the incoming air passes through the ceramic core until it is cooled, then as the fan changes direction it is warmed again by exhausting stale air. By having two synchronized units the air pressure in the house stays balanced. You can see a DIY Lunos Ductless ERV installation video here.