RM – Auto Shut Off Troubleshooting

Apr. 4th, 2024 | David Soohoo

Follow this help article if you are having trouble with your gas rice cooker’s auto shut off feature.

Applicable Models
  • RM-55N-R
  • RM-55P-R
  • RM-50N-R
  • RM-50P-R

Technical documents such as manuals and exploded diagrams can be found here.

 

Reported Issues / Complaints
  1. Main burner does not turn off automatically, leading to overcooked or burnt rice.
  2. Main burner shuts off too early, leading to uncooked, crunchy, or mushy rice.
  3. The #2 button does not stay down when the pot is mounted inside the rice cooker, but does stay down if the pot is removed.
Operational Synopsis

There is a bimetallic sensor (item # 56854) embedded underneath the pot.  It resembles a bottle cap.  When the water boils off, the temperature rises above the boiling point, causing the sensor to *pop* or *click*.  When this happens, it hits the shut off stem assembly (item # 56857), located in the middle of the unit’s base.  This action turns the main burner off, completing the cook cycle.  The pilot burner will stay on to help keep the cooked rice warm.

If you are having one or more of the problems noted above, the distance in between these two parts needs to be adjusted or otherwise corrected.

Bimetallic sensor

Item # 56854

Embedded underneath the rice pot

Shut off stem assembly

Item # 56857

Mounted in the middle of the base of the unit

 

If the main burner shuts off too soon, do not immediately press the #2 cook button a second time. 

If the cook button is immediately pressed again, the rice will burn.

The bimetallic sensor has activated and must cool down to be reset. 

You’ll hear a*click*  coming from the sensor when it resets.

 

DIAGNOSIS
  1. Turn the gas off by turning the black gas valve on the front of the unit to the vertical position.
  2. Remove the rice pot from the unit and set it aside.
  3. Push the shut off stem assembly down.  Make sure it springs back up with no issue and does not get stuck.
  4. Push down on the #1 button and then release it to allow it to pop back up.  During operation, you must always push the #1 button down before trying to push the #2 button.
  5. Push down on the #2 button.
  6. If the #2 button does not stay down, follow the steps in the #2 Button Troubleshooting guide.  If it does stay down, continue with this guide.

 

Solution

Verify that the jacket, pot, bimetallic sensor, and shut off stem assembly are all properly mounted and clean.  There should be no debris on or around the components and especially on the mating surfaces.  Clean, remount and adjust as necessary. 

  1. Jacket/Shroud
    1. The shroud has a twist lock mechanism.  Make sure it’s locked in at all three locations.
    2. Check that it’s sitting flat on top of the base and not tilted in any way.
  2. Pot
    1. Check that it’s sitting flat on top of the jacket and not tilted in any way.
  3. Sensor
    1. This can be caked with dirt and debris, not allowing it to adequately pop, or improperly mounted.  Clean, remount or adjust as necessary. 
  4. Shut off stem assembly
    1. This can be worn down, bent, or improperly mounted. Clean, remount, or adjust as necessary. 

If no issues are found, or issues were corrected and the problem persists, you can elect to follow the troubleshooting steps below, or simply replace both the sensor and shut off stem assembly.

To further troubleshoot, we can determine if the bimetallic sensor is operating properly.

  1. With the pilot lit and an empty rice pot in the cooker, press the #2 button to light the main burner.
  2. Expect to hear a click at around 3-4 minutes. The click is the sound of the sensor reaching shut off temperature.
  3. Pour a gallon of water into the rice pot and listen for the click of the bimetallic sensor returning to its cooking position.

If you only hear one click or no clicks at all, you will need to replace the bimetallic sensor (item # 56854).  If you hear both clicks, the sensor is working properly.  We can now try to adjust the distance between the parts.

  1. Locate the 3 leveling bolts on the underside of the pot.
  2. Use a wrench to loosen each bolt by one full rotation.
  3. Conduct the verification steps below to see if the issue is resolved.
  4. Repeat steps 1-3 up to 3 times.
  5. If the problem is not resolved, return the leveling bolts to the original positions.
Leveling bolts underneath the rice pot

 

If you do not hear both clicks, you will need to obtain replacement parts.  We recommend obtaining both the bimetallic sensor, and the shut off assembly, and replacing them as necessary.  They are relatively inexpensive and can be replaced with basic tools.  It’s discussed and shown in our RM series instructional video: RM-55 Overview.

 

Steps to verify proper operation
  1. Fill the pot with a gallon of water.
  2. Light the pilot, start the main burner and cover the rice pot.  Allow the water to boil for 10 minutes.
  3. Remove the cover and allow the water to evaporate.
  4. If the main burner shuts off a couple minutes after the water has evaporated, the unit is working properly.

 

 

Purchasing parts

Parts such as the shut off stem assembly and the bimetallic sensor may be purchased from your local food service equipment dealer (such as the one you purchased the appliance from) or from online e-retailers such as Parts Town.

 

RM-55 & RM-50 Product Overview Video

 

Still having problems?

Town’s commercial gas rice cookers carry a 6 month mail in warrantyIf your unit is under warranty, submit a repair request inquiry and we’ll be glad to assist.

We’ll process an RMA, and send you details for warranty repair. Per the warranty terms, the customer will be responsible for shipping the unit back to a designated repair facility. The original packaging must be used if available. Town is not liable for shipping damage due to insufficient packaging. If the issue is covered under warranty, Town will take care of all diagnostic, repair, and return shipping costs. We will ship the repaired unit to the shipping address provided. You may find more about our mail in warranty here.

We do not have a loaner program and recommend having a backup rice cooker for restaurants in which rice is a staple.

 

Warranty Repair Request                             View Rice Cookers