Ao Smith 100109929 Ignition Control Natural Gas Propane

Product Description

The AO SMITH 100109929 is a Honeywell-manufactured intermittent ignition device (IID) control designed for residential and light-commercial water heater heating systems. This control manages the ignition sequence for both natural gas (NG) and liquid propane (LP) fuel types, making it a versatile replacement component for gas-fired water heater applications. It is typically installed or replaced by a licensed plumber or gas appliance technician during routine service or when a no-ignition fault is diagnosed. The IID control coordinates the gas valve signal and igniter timing to establish and prove a stable pilot or main burner flame.

This control is suited for gas-fired water heater installations running on either natural gas or propane supply. It is specified for use with AO SMITH water heater models BTL 120, 154, 180, 198, 199, 250, 275, 310, 366, 400. These are commercial-style storage water heater units, making this control a direct-fit OEM-style replacement for those model lines. Technicians servicing any of these units experiencing intermittent ignition faults or control board failure should verify this part number against the unit data plate before ordering.

Key Features

• Compatible with both natural gas (NG) and liquid propane (LP) fuel types
• Intermittent ignition device (IID) control for gas-fired water heater systems
• Direct OEM-style replacement for specified AO SMITH BTL model series
• Honeywell-manufactured control module for reliable ignition sequencing
• Heating application — designed specifically for gas appliance ignition control

Compatibility

Specified for use with AO SMITH water heater models BTL 120, 154, 180, 198, 199, 250, 275, 310, 366, and 400 running on natural gas or propane fuel.

Installation Notes

Installation and replacement of gas appliance ignition controls should be performed by a licensed plumber or qualified gas appliance technician in accordance with local codes and IFGC requirements. Shut off the gas supply and disconnect electrical power to the water heater before beginning any service work on the ignition control. Inspect all wiring harness connectors for corrosion or damage before reconnecting to the new control. After installation, verify proper ignition sequence and flame-proving operation before returning the unit to service.

Technical Specifications

• Application: Heating
• Fuel Type: Natural Gas (NG) and Propane (LP)
• Control Type: Intermittent Ignition Device (IID)

Standard Information

• Brand: AO SMITH
• Manufacturer Part Number: 100109929