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Introduces the manual for the On Demand Water Heater.
Highlights immediate dangers like fire, explosion, and gas leaks.
Covers essential safety measures, including fire, explosion, and gas risks.
Provides a description of the On Demand Water Heater's functionality.
Safety guidelines specific to operating the water heater, including gas leak procedures.
Step-by-step guide on how to operate the water heater.
Guidance on operating faucets and showers for optimal hot water delivery.
Steps for properly shutting down the water heater unit.
Critical safety advice and warnings for performing maintenance and repairs.
Procedures for protecting the unit from freezing temperatures during storage.
Information on descaling the heat exchanger and the function of the pressure relief valve.
Step-by-step instructions for removing the water heater unit from the RV.
Guidance on obtaining replacement parts and contacting authorized service centers.
Technical specifications for the ST-42 and ST-60 models.
Details on what the warranty covers, limitations, and items not covered by Suburban.
Steps to follow if a product issue arises, including contacting service centers.
Introduces the manual for the On Demand Water Heater.
Highlights immediate dangers like fire, explosion, and gas leaks.
Covers essential safety measures, including fire, explosion, and gas risks.
Provides a description of the On Demand Water Heater's functionality.
Safety guidelines specific to operating the water heater, including gas leak procedures.
Step-by-step guide on how to operate the water heater.
Guidance on operating faucets and showers for optimal hot water delivery.
Steps for properly shutting down the water heater unit.
Critical safety advice and warnings for performing maintenance and repairs.
Procedures for protecting the unit from freezing temperatures during storage.
Information on descaling the heat exchanger and the function of the pressure relief valve.
Step-by-step instructions for removing the water heater unit from the RV.
Guidance on obtaining replacement parts and contacting authorized service centers.
Technical specifications for the ST-42 and ST-60 models.
Details on what the warranty covers, limitations, and items not covered by Suburban.
Steps to follow if a product issue arises, including contacting service centers.
This document describes the operation and maintenance of the Suburban On Demand Water Heater, models ST-42 and ST-60, designed for installation in recreational vehicles. This direct vent gas water heater with direct spark ignition provides an endless supply of controlled outlet water temperature when hot water is requested by the user.
The water heater operates by sensing water flow when a hot water faucet or other plumbing fixture is opened. Upon sensing flow, it initiates a start-up sequence: the combustion air fan turns on, proper airflow is detected by the control unit, the combustion chamber is purged of any raw gas, and then the burner ignites. Successful burner ignition is confirmed by a flame sense electrode. The approximate time from turning on the faucet to ignition is 7 seconds, which reduces to about 5 seconds once the water heater is maintaining temperature. Hot water begins flowing approximately 3 seconds after ignition, though it may take longer to reach the faucet depending on the length of the hot water lines. The burners remain on until the water flow is shut off, at which point the water heater shuts down and enters a ready state. The blower motor continues to operate for about 20 seconds after the hot water faucet is turned off.
The system is designed to modulate burner output to accurately control the outlet water temperature. Under low flow conditions, a high BTU stage will disengage, and the unit will operate at a very low BTU, conserving propane and improving temperature control. The water heater is factory set to maintain a water temperature of 113°F (45°C), but this can be adjusted by the user between 95°F (35°C) and 131°F (55°C) using the UP or DOWN arrows on the User Control Panel. A child lock feature prevents the outlet water temperature from exceeding 122°F (50°C), which can be overridden by holding the UP arrow for five seconds.
The water heater incorporates several safety features:
To operate the water heater:
To turn off the water heater:
Regular maintenance is crucial for safe and efficient operation. All repairs and maintenance should be performed by a dealer or a qualified service technician.
Safety Precautions for Maintenance:
Draining and Storage Instructions (Winterization): If the RV is to be stored during winter months, the water heater system must be drained to prevent freezing damage.
Descaling Information: Annually, drain the water from the system and flush the heat exchanger with an approved descaling solution.
Pressure Relief Valve: The pressure relief valve is designed to open if water pressure reaches 150 PSI/1034 kPa. If it discharges periodically, it may be due to thermal expansion in a closed water supply system. Contact the water supplier or local plumbing inspector for correction. Do not install any plumbing on the discharge port of the relief valve.
Removing the On Demand Water Heater:
An odorant is added to the gas used by this water heater to aid in leak detection.
General| BTU | 42, 000 BTU |
|---|---|
| Fuel Type | LP Gas |
| Input BTU | 42, 000 BTU |
| Water Heater Type | Tank |
| Ignition | Electronic |
| Ignition Type | Direct Spark |
