When should you replace an HRV or ERV to protect indoor air quality?
Our home was built in '45, most things updated in 60's/70's but with my health issues need to continue improving air quality- some return air/vents were completely blocked off by some not very intelligent homeowners - so air isn't moving properly in home.
The electric isn't grounded (tech North America's electrical grounding isn't grounded properly anyway (need to lower EMFs), gain access to attic, remediate, add air exchanger (with filter and dehumidifier if that's possible?). Anyway, a bio-home inspector would be ideal but all funds need to go towards the actual updates. HVAC right now is not efficient, full of dirt (despite having cleaned) and new furnace/AC with extra filtration and UV light. Without knocking down the house, is there a way to replace old metal dirty hvac (suspect mold caught in joints etc.)? Local HCAV didn't offer a good suggestion - just air exchanger and that's not enough... need to remove source of issues.
Also welcome the best insulation (in Ontario) for cubbies 16", 2-3" thick. Has to be super clean, no off gassing, mold resistent.
Also, suggestions for best air exchanger set up for someone with chemical and mold sensitivies.
And any tips on setting up proper air pressure for air flow in home, don't want the attic air coming into home which I suspect is happening.