When your Tuttnauer autoclave starts flashing error codes your first reaction is probably panic. Your autoclave is one of the most important pieces of equipment you have and without it you can’t sterilize your tools. And if you can’t sterilize your tools you’re out of business. Don’t worry though. A Low Temp error code is no cause for alarm. And you can probably repair the problem yourself.
A Low Temp error code is displayed if the temperature in the chamber starts to drop. If the temperature drops more than 4.5ºF the sensor will automatically abort the cycle and the Cycle Fail indicator lights will also flash. All those flashing lights make the situation appear like the plane is about to crash and everyone needs to grab a parachute. But it’s just a little turbulence. Hang on. You can fix it.
First, check the water level in the chamber. If there’s not enough water in the chamber then there won’t be enough steam and steam is necessary to create the heat that sterilizes your tools. Here are some things to check:
- Check the water level in the reservoir to make sure it’s full
- Be sure your autoclave is properly leveled
- Check the water sensing electrode for dirt or it may be shorted out
- Make sure the water pump isn’t clogged
- Look for clogged water lines
- Make sure the air outlet valve is working properly
Next, if the water level in the chamber is fine, check your cycle time. If the cycle was set for too long a period of time the water in the chamber may have boiled out and that’s why the chamber is dry. This happens often, especially on autoclaves with manual set timers.
It it’s not a timer problem, you then need to check the safety thermostat. It may be defective. When the safety thermostat opens it automatically turns of the heating elements – as a safety precaution. In the Tuttnauer T935N5 and T935N6 autoclaves the safety thermostat has been known to open prematurely.
You should never attempt to recalibrate the safety thermostat. It was calibrated at the factory and should be replaced with another factory calibrated thermostat. That said, you can replace that thermostat yourself.
Unplug your autoclave first and then remove the wires from the terminals on the thermostat. You’ll want to tag them so you can easily reconnect the replacement. Next, remove the screws or unscrew the lock holding the safety thermostat to the mounting bracket. Loosen the bolts on that hold the thermostat to the heating element and remove the probe. Be careful when uncoiling the tubing that connects the probe to the contact body. It’s filled with liquid and if you puncture it you’ll need to replace it, too.
Now, just mount the new thermostat and run a test cycle to make sure everything’s working properly again.
As you can see, there’s really no need to panic when your Tuttnauer autoclave displays a Low Temp error code. It’s easy to repair the problem yourself. In fact, it’s just as easy to take care of just about any problem you have with your autoclave. So don’t let all those flashing lights scare you. Pick up a wrench and fix it yourself.