Tankless Water Heaters & Safety

Make sure your tankless water heater runs safely with these tips and support.

For over 73 years, State has developed a strong tradition of innovative water heaters that operate safely within your home or business. Even if your water heater isn't top of mind most of the time, making sure you are familiar with safety measures during use and installation is crucial. State's water heaters are tested for toughness and durability and engineered with innovative features that can detect problems before they occur. Look below for a complete guide to the features and safety measures that State incorporates into all tank water heaters.

How We Keep Your Water Heater Safe

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Air-Fuel Ratio (AFR) Sensor

Tankless water heaters monitor and adjust their fan speeds to ensure that air and fuel remain mixed at the correct ratio. This is important to ensure proper combustion occurs at all times. This actively reduces emissions and increases efficiency.


Exhaust temperatures are monitored by your indoor condensing water heater to ensure that it operates at a safe level for PVC venting. If temperatures reach unsafe levels, combustion is regulated by the thermistor and hi-limit switch. These can even turn the water heater off to protect the venting material from damage. Learn more about vent configurations.

Hi-Limit Switch

The hi-limit switch uses data from the inlet and outlet thermistors to make sure the water is at an appropriate temperature. If measurements exceed 185° F or 194° F, the hi-limit switch shuts down your tankless water heater by disengaging gas valves.

Freeze Protection

With an internal freeze protection system, tankless water heaters use electric heaters to prevent the heat exchanger's temperature from dropping too low. Some models boast additional protection that allows the burner to fire for a few seconds. These features reduce the chance of freeze damage. However, we recommend that a tankless water heater be installed indoors if you live in a cold climate so that it is not exposed directly to freezing temperatures.

Overheat Cutoff Fuse

Tankless water heaters are protected by a built-in overheat cut off fuse that disengages the gas valve if there is a breach in the heat exchanger wall or gaskets around the combustion box.

Additional Reading

State water heaters come in a large range of sizes. Discover the factors to consider when making your decisions.

Learn more about water heater sizingkeyboard_arrow_right

How can the quality of your water affect your water heater? Get tips and more information on water hardness, why it matters, and how to solve it.

Learn how water quality affects water heaterskeyboard_arrow_right

Gas water heaters require venting upon installation. Depending on your home, there are many different options.

Learn about vent configurationskeyboard_arrow_right
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