Return to site to complete duct clean and sanitization. Hrv and returns were quite severely built up so I thuroughly cleaned to make sure all dust and debris removed Re assemble system and make sure power is on Clean dryer duct (top floor) re assemble and put back into place Clients home is very clean at all times but struggle with dust in system so I’m hopeful a good cleaning will resolve issues but another cleaning in approx 3 years may be required to keep caught up on dust build up