Home Products Motorized Dampers HOM - Combustion Air Damper

HOM - Combustion Air Damper

HMI HOM Series 
- Fresh Air Damper for Combustion Air Control -  

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NEW! VIDEO - Click here to view  
Shell Busey and Cliff Hoyme explain the HOM Damper in a video from our archives. 


HOM sizes range from 4

HOM Series dampers automatically control fresh air for combustion in residential and commercial buildings. Sizes range from 4" to 9" diameters in increments of 1". For larger commercial sizes, several dampers are mounted in tandem with end switches connected in series. May be used for retrofit and new installations.

Passive fresh air inlet ducts waste energy, are sometimes plugged and therefore become unsafe. Alternatively,
HMI HOYME Motorized Dampers are safe as there is no need to plug the duct. The result is added comfort, added safety and a saving in energy costs .

Series HOM dampers are connected to the appliance transformer and are power closed. When the appliance fires, the damper drops open by gravity and does not interfere with appliance transformer.

CSA International Certified. Satisfaction guaranteed.

HOM- Combustion Air Damper - Typical Residential Installation   HOM- Combustion Air Dampers - Commercial Installation


Features Include:

  • Simple to install, attaches to the terminating end of insulated air supply duct.
  • Interlocks with the safety control system of gas, propane and oil fired appliances which guarantees the damper to be open before the fire starts.
  • Certified as required by National Gas Codes ; fail-safe open, power closed.
  • Durable, patented HMI   'spring motor drive' with nylon bearings.
  • Standard connection to 24Vac thermo/aqua-stat circuits plus, with the use of 'Interface Relay Adaptors' , damper is compatible with MilliVolt DC and 120 Vac safety control systems.

Options Include:


1. Additional Relay and end-proving-switch to control two appliances (SF2).
2. Interface Relay Adaptors to provide interlocking connection to Millivolt DC and Line Voltage AC controls for commercial buildings. 
3. TEST/RUN switch (Standard equipment) to automatically disconnect circuits for testing damper and appliance operation. 
General Damper Identification: i.e HOM-0511-SF1


Diameter (in)



End Switch


No. of switches/furnaces








Colored Wire Diagrams used with the HOM Series Dampers

SF1 - One Appliance Model


SF2 - Two Appliance Model

Last Updated (Wednesday, 07 October 2015 14:26)