Cost of Air Conditioner Installation in Maryland$5,280.15 for 2-3 ton unit (using existing ductwork) (Range: $4,559.78 - $6,000.52) Free Estimates from Local ProsCost of Whole House Humidifier Installation in Maryland$513.45 for mid-grade central humidifer (flow-through) (Range: $471.30 - $555.60) Free Estimates from Local ProsCost of Central Air Purifier Installation in Maryland$1,431.80 for a typical two story home (standard grade unit) (Range: $1,204.45 - $1,659.15) Free Estimates from Local Pros |