Aprilaire Humidifier 500MK

Aprilaire Humidifier 500MK





  • HUMIDITY FOR HEALTH AprilAire Humidifiers can help you maintain optimal humidity in your home which has been shown to reduce the incidence of respiratory infections and symptoms related to allergies and asthma by minimizing the formation of bacteria and viruses.
  • PROTECT YOUR HOME Preserve your home and any contents susceptible to damage from changing humidity or dry conditions.
  • HUMIDITY FOR COMFORT Balance your humidity to preserve your home and protect its occupants from dry air issues like static shock and chapped skin.
  • BUY WITH CONFIDENCE This humidifier was designed and manufactured in the USA by AprilAire—the inventor of the whole-house evaporative humidifier, and the leader in Indoor Air Quality since 1954.
  • ONBOARD CONTROL SENSOR Automatically turns on the HVAC fan to measure the relative humidity inside the ductwork and from all parts of the home. Turns on the humidifier whenever the measured humidity drops below the set point.
  • FULL COVERAGE For tightly constructed homes up to 3,500 square feet, with a capacity of 12 gallons per day.*
  • CONVENIENT CONTROL To monitor and adjust the humidity with a high-contrast digital screen.


  • Manufacturer: Research Products Corp.
  • Brand Name:   Aprilaire 
  • Model:   500MK
  • Category: Water / Small ByPass / Flow Through
  • Rated Capacity:  12 gallons / day
  • Supply Voltage Required: 24VAC
  • Manufacturers’ Order Number:  500MK
  • Included Humidifier Control Type (Humidistat) : Mechanical
  • Humidistat Part Number: RP4655
  • Plenum Opening Required: W= 9.5″  H= 9.5″
  • Water Efficiency Level: 25%
  • Floor Drain Required: YES
  • Maintenance Schedule (minimum) : Yearly 
  • Consumables Water Pad Number:  Part # 10
  • Humidifier Nominal Size: W= 16″  H= 13″ D= 10.25″
  • Unit Weight: 11 lbs.
  • Manufacturers’ Warranty: 5 Years