Suburban 5581A Advantage® Tankless, Continuous Water Heater

Microprocessor-controlled, self-modulating, combustion system regulates LP gas input from the 36,000 BTU/h first stage and the 60,000 BTU/h second stage to maintain the desired temperature setting. Has a maximum setpoint temp of 130° F. Also has Active and Passive Freeze Protection. When the sensor detects water approaching freezing, and LP gas and power are available, the burner intermittently cycles. If gas or power is not available, passive freeze protection allows water to drain.