When your Girard GSWH-2 tankless water heater won't ignite or produces inconsistent hot water, a failed flow switch is one of the most common culprits. This is the genuine OEM-specification replacement -- part number GIR2022107580 -- that restores the flow-sensing function required to trigger the burner and deliver reliable hot water in your RV.
The Girard GSWH-2 is a propane-fired, on-demand tankless water heater used extensively in towable and motorized RVs. Its flow switch is a critical trigger component: when water movement is detected above the minimum activation threshold, the switch signals the control board to open the gas valve and fire the igniter. A worn, corroded, or stuck flow switch interrupts that signal chain -- resulting in no ignition, fault codes, or unpredictable burner behavior.
The 2GWH-20 is a direct OEM-spec replacement. At 3.5 inches in length and just 0.3 lbs., it installs into the same port without modification. No adapter fittings, no re-wiring, no recalibration of the control board required.
Designed to the exact specifications of the original GSWH-2 flow switch. Drops in without adapters or modifications.
Detects water movement and sends the activation signal to the GSWH-2 control board, enabling ignition on demand.
Manufactured to meet Girard quality standards for the GSWH-2 platform -- same sourcing as the original production unit.
Compact, lightweight design. Accessible with basic hand tools and no specialized equipment in most GSWH-2 installations.
Flow switches in tankless water heaters are exposed to mineral deposits, sediment, and the constant mechanical stress of water pressure cycling. Over time, the internal paddle or reed mechanism can stick, corrode, or lose sensitivity. When that happens, the heater either refuses to ignite or fires erratically. Common symptoms that point to the flow switch rather than the igniter or gas valve include:
The flow switch on the GSWH-2 is typically located in the cold-water inlet path of the heater assembly. Installation involves depressurizing the water system, removing the old switch from its threaded port, installing the 2GWH-20, reconnecting the wiring harness connector, and restoring water pressure before testing ignition. No soldering or board-level work is required.