Priorities in Retrofitting System
Brief history - Approximately 3 years I developed severe allergies, especially to indoor allergens. I'm allergic to just about everything, but normally feel worse inside. As such, it's been an ongoing battle to keep indoor air the highest quality possible. I recently changed residences. The current house is appx 15 years old, single story, a little bit over 3,000 sq ft. It has an electric forced air system with 3 blower units in the attic crawlspace. The home also has blown cellulose insulation and recessed lighting, which I believe is aggravating my allergies since every time the HVAC kicks on it seems to make my symptoms significantly worse.
My question is, in designing a new system, what would everyone consider the steps/components I should take, starting with the highest priority?
I've done the basics prior to moving in - professionally cleaned ducts/blower fan/evap coils & changed the return duct filters to 4" pleated MERV13. In my previous home I had an Aprilaire Model 5000 air cleaner, Aprilaire 800 Steam Humidifier, and Aprilaire 8126 Ventilation System. I live in the desert in the Southwest region of the country, so excessive humidity is never an issue. Without the steam humidifier my home was between 15-25% RH; with the humidifier, I kept it between 35-40% RH.
Thank you in advance for any replies and/or suggestions. This site is extremely informative and I'm glad to have found it.
**P.S. - I've already searched my area for a contractor through ComfortInstitute and BPI and was unfortunately unable to find anyone within 50 miles.