Remove & Replace The Tuttnauer 2540 Series Safety Thermostat

Tuttnauer 2540 Series Safety Thermostat Replacement

Tuttnauer Automatic Reset Safety Thermostat Tuttnauer Automatic Reset Safety Thermostat

(Installation and replacement procedures are identical for both the Safety Thermostat and the Cut-Out Thermostat)


This Thermostat is calibrated at the factory and does not require calibration

Tampering with the adjustment on this thermostat will totally defeat the safety feature.

The only recommendation is that a defective thermostat be replaced with a factory calibrated replacement.

Removing The Old Safety Thermostat
  1. Unplug the unit
  2. Remove the wires from the terminals

  3. Tech Tip: Tag Each Wire As It Is Removed To Simplify Reconnecting To The New Safety Thermostat

  4. Remove the two screws holding the Safety Thermostat to the mounting bracket, or unscrew the lock nut, which ever method is being used to secure the thermostat
  5. Loosen the bolts on the rear most Heating Element or which ever element the probe is held in place by. Remove the probe

Installing The New Safety Thermostat

  1. Carefully uncoil the tubing connecting the probe to the contact body

  2. The probes and the tubing leading to the body of the thermostat are filled with liquid. It is important that while working with these sensors that the tubing not be kinked.

    If the tubing is kinked or the probe punctured the device will not work and should be replaced.

  3. Mount the new thermostat body using the screws or lock nut that were removed in step 3 above.
  4. Carefully route the probe and tubing over to the rear Heating Element
  5. The new probe should be installed in the proper channel on the rear most Heating Element, regardless of what element the probe was under originally

  6. The Safety Thermostat is in the lower channel

    The Cut-Out Thermostat is in the upper channel

    The body of the Cut-Out Thermostat is mounted on the top portion of the mounting bracket.
    The body of the Safety Thermostat is mounted on the bottom portion of the mounting bracket.

    NOTE: Improper mounting of the probes will result in a malfunctioning of the autoclave.

    If the replacement thermostat has a long probe it is only necessary to secure the rear portion of the probe under the rear most element.

  7. Retighten the Heating Element making sure that the probe is held securely between the element and the Chamber.

  8. It is important that the probes be snug in channels of the Heating Elements. If they are loose they will not make good contact with the Chamber and well not properly sense the temperature.

    Flattening the channel on the Heating Element slightly is an acceptable way of snugging the probe.

  9. Reconnect the wires to the same terminals that they were removed them

  10. Be careful not to connect a high voltage wire to the ground terminal.

    If the replacement thermostat does not have a separate ground terminal then the ground wire need not be connected. Screwing the thermostat to the mounting bracket will supply sufficient grounding.