The Fenwal 35-605606-227 is a direct spark ignition (DSI) control module engineered as a drop-in replacement for Johnson Controls G76x series ignition modules. It matches the original footprint, mounting hole pattern, and wiring connections exactly -- no adapters, no bracket fabrication, no rewiring gymnastics. Also sold under NBK part number 20460. Suitable for commercial cooking equipment, gas furnaces, unit heaters, and water heaters operating on natural gas, LP, or manufactured gas.
When a Johnson G76x series ignition control fails, finding an exact OEM replacement can be a frustrating, time-consuming search. The Fenwal 35-605606-227 eliminates that problem. It is purpose-built to substitute directly for the G76x family, matching every mechanical and electrical interface so your appliance is back in service quickly.
Full-time flame sensing and a fast 0.8-second flame failure response mean the module detects ignition problems immediately and responds before unsafe gas accumulation can occur. Conformal coating on the circuit board provides moisture resistance up to 95% relative humidity (non-condensing), making this module suitable for demanding environments including marine and RV installations.
Identical footprint, mounting hole pattern, and wiring connections to the Johnson G76x series. No modifications needed.
Safe-start and continuous flame monitoring with a 0.8-second maximum flame failure response or re-ignition time.
Pre-purge and interpurge timings of 30 seconds each (this configuration). Multiple trial-for-ignition period options available across the 35-605606 series.
Conformal coating allows operation up to 95% relative humidity (non-condensing) -- built for tough environments.
The 35-605606-227 runs a 30-second pre-purge before attempting ignition, clears the combustion chamber, then opens the gas valve and fires the spark for a 15-second trial-for-ignition window. An interpurge of 30 seconds separates each attempt. The module supports either one or three ignition trials depending on configuration. If ignition is not established within the allowed trials, the module locks out and waits for an automatic reset -- either 5 minutes or 1 hour, depending on jumper setting.
The flame detector self-check runs at a minimum rate of once per second, and flame sensitivity is rated at 0.3 microamps minimum, ensuring reliable detection even with marginal flame quality.
The 35-605606-227 supports both remote and local flame sense configurations. In remote sense mode, spark rate is synchronized to line frequency (50 or 60 Hz). In local sense mode, the spark rate runs at 25 or 30 Hz. Choose the mode that matches your original equipment setup -- both are supported without hardware changes beyond the flame sense lead routing.