The Suburban ST-42 On-Demand LP Gas Tankless Water Heater (5391A) from Nomadic Supply Company® delivers 42,000 BTU of on-demand propane-powered hot water for RVs, van conversions, truck campers, and off-grid setups. Unlike traditional tank heaters, the Suburban ST-42 On-Demand LP Gas Tankless Water Heater (5391A) fires its burners only when hot water is demanded, eliminating standby heat loss and conserving propane across every trip.
Seven integrated safety systems protect you and your family at every use. Flame-out protection with automatic gas cutoff shuts off fuel if the burner is unexpectedly extinguished. A high-temperature kill switch prevents scalding, while the child lock caps outlet temperature at a safe 113°F maximum. Active freeze protection, automatic fan monitoring, an integrated pressure relief valve, and a voltage protection system complete the safety suite. Direct spark ignition eliminates the standing pilot light, and the included digital control center wall mount puts precise temperature control at your fingertips.
The Suburban ST-42 On-Demand LP Gas Tankless Water Heater (5391A) is a non-portable unit designed for permanent installation in an RV appliance bay. The access door is sold separately, giving you the flexibility to select the cover that fits your coach. This model also replaces the discontinued Suburban 5381A, making it a straightforward upgrade for existing installations.
Suburban ST-42 On-Demand LP Gas Tankless Water Heater (5391A) Features:
- 42,000 BTU On-Demand LP Gas: Delivers continuous, endless hot water only when needed – no standby heat loss and no waiting for a tank to reheat.
- Flame-Out Protection: Automatic gas cutoff activates if the burner flame is unexpectedly lost, preventing unburned propane from accumulating.
- Scald Protection: High-temperature kill switch monitors outlet water temperature and shuts down the unit before water reaches dangerous levels.
- Child Lock: Limits maximum outlet temperature to 113°F, providing a critical safety barrier for families traveling with young children.
- Active Freeze Protection: Built-in freeze-protection circuit activates automatically when ambient temperatures drop, protecting internal components from cold-weather damage.
- Automatic Fan Monitoring: Continuously verifies the exhaust fan is operating correctly and halts burner operation if an anomaly is detected.
- Integrated Pressure Relief Valve: Factory-installed pressure relief provides an additional layer of system protection without a separate installation step.
- Voltage Protection System: Guards the unit electronics against power fluctuations common in RV shore-power and generator environments.
- Direct Spark Ignition: Eliminates the standing pilot light found on older models, improving efficiency and simplifying day-to-day operation.
- Digital Control Center Wall Mount Included: Provides intuitive temperature adjustment and system feedback from your living area.
- Replaces 5381A: Drop-in upgrade for existing Suburban 5381A installations – same footprint, updated electronics and safety systems.
- 2-Year Limited Warranty: Backed by Suburban manufacturer warranty for peace of mind on the road.
Suburban ST-42 On-Demand LP Gas Tankless Water Heater (5391A) Specifications:
- BTU Output: 42,000 BTU
- Fuel Type: LP Gas (Propane)
- Type: Tankless, On-Demand
- Ignition: Direct Spark
- Max Outlet Temperature: 113°F (child lock engaged)
- Product Dimensions: 12.5 in. H x 12.75 in. W x 13 in. D
- Product Weight: 19 lbs (without door)
- UPC: 755790724420
- Warranty: 2 Years Limited
