Promotional value expires 90 days after purchase. Amount paid never expires. Appointment required, 48 hour advance notice required. Appointment required. Merchant's standard cancellation policy applies (any fees not to exceed Groupon price). Limit 1 per person, may buy 1 additional as gift. Limit 1 per visit. Limit 1 per household. Valid only for option purchased. All vents must be serviced. Valid for cleaning of 1 furnace and up to 8 vents. Voucher also includes a $50 gift certificate towards the purchase of each one of the following items: electrostatic filter / sanitizer combination or humidifier installation. Includes $20 credit towards carpet cleaning. Merchant is solely responsible to purchasers for the care and quality of the advertised goods and services. Learn about Strike-Through Pricing and Savings