Can I Bypass A Thermal Switch On A Water Heater?

Can I Bypass A Thermal Switch On A Water Heater?

Water heaters provide an efficient, cost-effective way of swiftly and conveniently heating water across multiple houses. Traditional heating systems, on the other hand, might be costly and cause extra headaches due to thermal switch concerns.

If your water heater produces cold water throughout the winter, one possible solution is to bypass its thermal switch. While repairing such switches would undoubtedly result in faster and more consistent heating of your home, bypassing it may bring temporary respite.

Are you trying to bypass the thermal switch on your heating unit? This article describes fixing a broken thermal switch in a water heater.

What Purpose Does a Thermal Switch Serve?

A thermal switch, also known as a thermal cut-off switch, is an electromechanical device that controls electrical flow based on temperature fluctuations by activating or deactivating it at the right time.

In-home and commercial settings switches that trip when temperatures surpass a predefined threshold protect against failure or overheating. These valuable devices should not be overlooked.

Thermal switches are commonly used in residential appliances such as tankless water heaters and dryers; however, advanced technology is used in commercial and industrial applications such as commercial jetliners.

A standard home water heater’s thermal cut-off switch can be manually reset in front of the combustion chamber door.

Also, Read: What Size Tankless Water Heater For Mobile Home?

Why Shouldn’t You Use A Thermal Switch?

Before bypassing a switch, consider the following:

  1. Extreme heat could cause your water tank to overheat and overflow without a thermal switch, resulting in catastrophic injury and property damage.
  2. Burns and other serious injuries are possible if the water is hot. A thermal switch keeps the temperature of a gadget within a safe operating range.
  3. Furthermore, extreme heat might harm tank and unit components. Thermal expansion accelerates wear and tear, resulting in costly repairs. A switch keeps the heater from overheating, extending its useful life.
  4. Switches improve equipment’s energy efficiency. Water heaters would have to work much harder to maintain stable temperatures without them, consuming far more energy because their cycles lasted far longer than expected.

Why Should You Disable Your Water Heater’s Thermal Switch?

After analyzing the potential benefits of installing a thermal switch in your water heater, we advocate using it only when necessary. Here are three compelling reasons to bypass its Thermal Switch:

Thermal Switch Malfunction:

If a thermal switch continues to trip within its permissible temperature range, bypassing it may be one option for restoring hot water to your home; however, replacing it as soon as possible is desirable.

Rising Water Demand:

Keeping up with increasing demand can quickly deplete resources.

If there is an immediate demand for hot water, it may be necessary to bypass the switch to provide extended periods of hotter water.


It may be feasible to temporarily bypass the thermal switch to determine if it is faulty or if there is another issue with your water heater system.

Also, Read: How To Tell If Water Heater Is Gas Or Electric?

Is it safe to bypass thermal switches?

Although bypassing thermal switches may appear risky, their relevance and utility cannot be overstated when safety is paramount.

Thermal switches safeguard you from potential water heater hazards; for example, if burning gas valves become jammed, they will activate, preventing an explosion. Although bypassing thermal switches on water heaters is possible, it comes with several risks and should only be attempted at your own risk.

The Benefits and Drawbacks of Bypassing:

It is never recommended to bypass a thermal switch without thoroughly investigating its potential consequences and implications; bypassing it has both risks and benefits that should be carefully considered before taking such action.

Perilous Situation:

A thermal switch prevents water heaters from reaching potentially dangerous temperatures. Bypassing this safeguard raises the risk of overheating, resulting in a fire or other consequences, such as harm to employees or neighbors.

Your warranty is null and void:

Bypassing a thermal switch may ruin a water heater’s warranty; most manufacturers consider tampering with safety components to void warranties.

Legal Implications:

Bypassing water heater safety safeguards may contravene local building laws or regulations, resulting in legal implications or penalties if an accident occurs.

How to Turn Off a Water Heater’s Thermal Switch:

Never tamper with your heater’s thermal switch since it poses fire and electrocution hazards that only trained individuals should handle.

First, turn off the electricity to your switch by unplugging it. Turn off the power supply and circuit breaker for your water heater; for gas water heaters, turn off the gas supply and pilot light.

Locate and deactivate the thermal switch near the machine’s heating element or thermostat. Unplug any heater-connected cords before connecting two wires to a cable termination and turning it on.

A bypass kit is another option for bypassing the safety switch; however, the kit you choose will be determined by the model of your water heater.

Begin by disconnecting the appliance from its connections and turning off its power via the circuit breaker or gas supply. Connect wires from a bypass kit directly to the thermal switch terminals to ensure a secure electrical connection!

Connect the wires previously connected to the thermal switch to the bypass kit and test for continuity before turning on the water heater’s power.


When your water heater fails, bypassing its thermal switch may appear to be a simple and quick fix; nevertheless, poor handling can cause substantial damage to you and your home. So, always hire an expert before doing anything critical with the water heater.


Can I Turn Off My Water Heater?

Yes. To bypass a water heater, just close both the hot and cold valves on the plumbing lines before opening the bypass line valve; once accomplished, close this and reopen all hot/cold valves to restore normal operation.

Why does my water heater’s thermal switch keep tripping?

The reset button on a water heater may occasionally trip repeatedly. This signals a more significant issue that has to be investigated further, such as defective thermostats, loose electrical connections or corrosion on equipment, grounding concerns, or a nonresponsive high-limit switch.

What Does Heater Bypass Mean?

Some heaters use internal bypasses to control how much water flows through their core while sending out any excess flow. Other heaters’ external bypasses may prevent their maximum flow rate from being exceeded.


About Author

Mobeen Shahid

Mobeen Shahid

Mobeen Shahid is a Mechanical Engineer with two years of experience in the HVAC industry. His passion is analyzing HVAC issues, and he works relentlessly to devise customized solutions. He has been in the industry long enough to know the ins and outs and ensures that areas are optimally heated, cooled, and ventilated.

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