Honeywell ST7800A1039
The Honeywell ST7800A1039 30-Second Purge Timer is a plug-in timing module designed for use with select Honeywell 7800 Series burner management and flame safeguard relay modules.
This industrial combustion control accessory establishes a fixed 30-second prepurge timing period for compatible burner control applications. The prepurge process is an important part of the burner startup sequence, allowing the combustion system to complete its required ventilation cycle before proceeding with ignition.
As part of the Honeywell ST7800A Series, the ST7800A1039 provides a dedicated prepurge timing function. Its timing interval is established by the specific module part number rather than by an adjustable timer setting.
The Honeywell ST7800A1039 is intended for integration with compatible Honeywell 7800 Series relay modules. These control systems are commonly used in commercial and industrial combustion equipment requiring automatic burner sequencing, safety interlock monitoring, and flame supervision.
The timer works in conjunction with the relay module and the other elements of the burner management system. It does not independently operate the burner, monitor flame presence, or replace the safety functions performed by the primary control module.
During a normal burner startup sequence, the relay module evaluates the required operating conditions and supervises the appropriate prepurge operation. The installed purge timer determines the designated timing interval used by the compatible control.
The ST7800A1039 provides a 30-second prepurge interval. The selected timing period must be appropriate for the specific burner equipment and comply with the applicable manufacturer requirements and combustion safety standards.
The plug-in design simplifies the physical installation of the timing module into the corresponding relay module compartment. It also supports replacement of an existing timing card when maintenance or equipment servicing is required.
The Honeywell 7800 Series includes multiple purge timer configurations with different prepurge durations. For this reason, replacement components must be selected by their exact manufacturer part numbers and required timing specifications.
The ST7800A1039 must not be confused with other Honeywell purge timer models that provide different timing intervals. Using the wrong timer may result in an incorrect burner startup sequence and could compromise compliance with the approved equipment configuration.
Typical applications include industrial steam boilers, commercial heating boilers, industrial gas burners, oil burner assemblies, combustion equipment, process heating systems, and other installations that utilize compatible Honeywell 7800 Series burner controls.
Industrial maintenance technicians and burner service contractors may use this component when servicing compatible combustion control systems or replacing an existing plug-in purge timer.
Before installing the Honeywell ST7800A1039, the technician should verify the relay module model, required prepurge duration, existing control configuration, and applicable safety documentation.
Installation should follow the official Honeywell instructions. After the component is installed, the complete burner control system should be tested through its required operating sequence by qualified personnel.
For applications involving the Honeywell RM7840L1018 or other compatible burner programmer controls, the ST7800A1039 may be used when the specific burner configuration requires and permits a 30-second prepurge period.
The Honeywell ST7800A1039 is a separate plug-in component and should not be assumed to be included when purchasing a relay module.
JJC Global Group LLC supplies Honeywell combustion control components, burner management accessories, industrial automation products, and replacement parts for industrial maintenance and equipment servicing.
Customers can request a quotation for the Honeywell ST7800A1039 through JJC Global Group LLC for equipment replacement, industrial maintenance, and combustion control applications.
Contact JJC Global Group LLC for product information and quotation requests related to the Honeywell ST7800A1039 30-Second Purge Timer.
For detailed technical specifications, compatible relay module information, and installation instructions, refer to the official Honeywell ST7800A Series Plug-In Purge Timer documentation.