Pilot light, or intermittent ignition device?
Some tankless gas water heaters have a pilot light, while others have something called an intermittent ignition device. Newer gas ovens use these devices, too, instead of relying on a pilot light. In general, the newer IID devices are recommended, since tankless gas water heaters with pilot lights must burn continuously and will offset some energy savings normally seen with the tankless water heaters. Flow rates Finally, you’ll need to determine what the flow rates of devices consuming hot water will be. This will determine the best model of tankless gas water heater for your purposes.
