Have to reset heater button - Little Giant Water Heaters

The Toyotomi OM122DW on-demand water heater typically doesn't have a physical reset button like some traditional tank-style water heaters. If you're experiencing issues with your water heater, there might be a few troubleshooting steps you can take:

1. Power Cycling: Turn off the power to the water heater by switching off the circuit breaker or unplugging it if it's a plug-in unit. Leave it off for a few minutes and then turn it back on. This action can sometimes reset the system and resolve minor issues.
2. Check for Error Codes or Indications: If your Toyotomi water heater has a digital display, it might show error codes or indications for any problems it's encountering. Consult the user manual for the OM122DW to understand what these codes mean and how to address them.
3. Inspect Gas Supply: Ensure that the gas supply to the water heater is uninterrupted and that the gas valve is fully open. If there are any issues with the gas supply, it might affect the water heater's performance.
4. Check Water Supply: Ensure that the water supply to the unit is adequate and that there are no blockages in the pipes leading to the water heater.
5. Contact Support: If you've tried these steps and the issue persists, it might be best to contact Toyotomi's customer support or a certified technician. They can provide specific guidance or schedule a service visit to diagnose and fix any issues with your water heater.

Regarding a physical reset button specifically labeled as such, it's important to consult the user manual as the location and method for resetting the unit can vary between different models and versions of the Toyotomi water heaters. If you don't have the manual, you might be able to find it online on Toyotomi's official website or by contacting their customer support.

Question edited for clarity. Looks like you encountered autocorrect

The manual is here. It doesn't mention a reset button.

Rheem RETEX-27 instruction manual and user guide

https://mans.io > Rheem > Tankless Electric Water Heaters

Rheem RETEX-27 Performance 27 kw Self-Modulating 5.27 GPM Tankless Electric Water Heater download pdf instruction manual and user guide.

But this says it does, or may have?

Where Is the Reset Button on a Rheem Hot Water Heater? On Rheem water heaters, the reset button is usually a red button located near the thermostat, at the middle of the limit switch. To access it, you will need to remove the metal panel on the unit. The red button is behind the insulation.

How to Reset Rheem Tankless Water Heater - Quick Fix

A typical answer for this·

1. Cut off power to the water heater at the panel·
2. Check the water heater reset button- The water heater reset button is the red button situated on the water radiator itself (simply over the indoor regulator). Some water heater may have two reset catches one for each indoor regulator. To get to the reset catch, you may need to evacuate the metal plate covering the indoor regulator that is held set up by screws. You may likewise need to evacuate a rectangular bit of froth protection to see the reset catch(button).
3.DO NOT reset if safety features continuously trip.

For More Information You Can Visit: https://www.indiapropertyclinic.com/services/water-heater-install-repair

Gas water heaters have thermal reset button located on front, electric heater located on upper thermostat ....
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html#parts
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html

No reset button.
The gas control valve is the thermostat
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Intellivent gas control can be reset, and Honeywell can be reset under some circumstances.
Otherwise, bad thermostat means replace gas control valve

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Reset button on gas water heater??
Usually there is not a reset button on gas water heater, which might explain why is doesn't move:

Do you mean the igniter button for lighting pilot?? The piezo igniter can go bad.

Copy following links for troubleshoot resources:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
http://www.thetankatwaterheaterrescue.com/forums/forum3/

Add comment with description of water heater, and more detail or call plumber.
Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Need a new thermostat to keep the unit from tripping

If I understand correctly the red reset button or ECO located on upper thermostat will not reset.
Add a comment if problem is different.

Electric water heaters are fully repairable by homeowner.
If circuit breaker to water heater will not reset, then you need full troubleshoot using inexpensive multi-meter from Home Depot::
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

If reset button will not reset, then two things can cause this problem.
1) Ground short between upper thermostat and upper element, including shorted upper element.
a) Look at wires to see visible signs of high heat and burning.
b) Test upper element for short.
http://waterheatertimer.org/How-to-test-water-heater-element.html

2) Upper thermostat is bad. Test upper thermostat, or just replace thermostat using generic upper thermostat from hardware store.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

3) If problems persist:
Troubleshoot electric water heater using inexpensive multi-meter from Home Depot:
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html


Upper thermostats are generic unless you have "energy-smart" water heater that has control box and reset button located on top of tank.

If I understand correctly, you have electric water heater.
Heater suddenly stopped heating.

Four things cause sudden loss of water heater.
1) Reset button located under the top cover is tripped > turn off power, remove cover, press reset button > if reset keeps tripping, go to the troubleshooting link shown below.
2) Electric power to heater is interrupted > check circuit breaker > test for voltage > look for loose wire on breaker
3) Upper element burned out > test and replace element
4) Upper thermostat bad > replace upper thermostat

Reset button is best suspect.
Here is a link for complete troubleshoot and homeowner repair of electric water heater:
http://waterheatertimer.org/How-to-troubleshoot-electric-water-heater.html

The top button is connected to the top heater element  which is likely shorting out. Drain the tank below the element that the thermostat is attached to. Remove and replace the element