Tuttnauer Autoclave Repair: What Causes The Add Water Error Code

It seems like it should be pretty easy to repair, right? Your Tuttnauer autoclave is giving you an error code that tells you to add water, so that probably means all you need to do is add some water. But when you take a look, you see the reservoir is already full. Now what?

Your autoclave is one of your most important pieces of equipment in your office and if something goes wrong it’s understandable that you would panic. You’re thinking of all the money it’s going to cost to send it out for repair, the expense of renting a replacement, and you might even have to close your office for a while.

When the sensors indicate that it should be an easy fix – like just adding some more water – and the easy fix doesn’t work, it can be frustrating. But don’t panic yet. Autoclaves only look intimidating. They’re really very simple pieces of equipment. There’s usually a very simple solution and most of the time you can do it yourself.

Check the model number on your autoclave. Tuttnauer’s most popular models are their E Series autoclaves, including the EZ9 and EZ10.

If you have an E Series model, then take a peek inside the water reservoir and you’ll see a float. This float is attached to a water level switch which acts just like a light switch – when you turn it on, the autoclave comes on, and when you turn it off, the autoclave turns off.

When everything’s working properly the water level in the reservoir lifts the float and it turns the switch to the ‘ON’ position, making an electrical connection which allows the power to run to your autoclave. When the water level is too low, the float disconnects with the switch, essentially turning your autoclave ‘OFF’ until you refill the reservoir.

When the water level is too low you’ll see that ‘Add Water’ indicator, or error message, light up on your display and, as a safety precaution, the unit will not come on again until you fill it with water. Which leads us back to the original problem.

In your case, the ‘Add Water’ message is flashing but the reservoir is full. Now what?

If the reservoir is full and the float is moving freely, then your problem is probably a defective water level switch. To be sure, you can run a simple continuity test by removing the wires and putting a probe from your meter (or continuity tester) to each wire.

With the meter set to test continuity:

  • When the float is in the Up position the meter should show continuity.
  • When the float is in the Down position the meter should show an open circuit.

Once you’ve verified that the problem is in the switch you can stop worrying. All you need to do is replace the switch and if you can use a wrench you can do it yourself. After you replace the water level switch in your Tuttnauer autoclave be sure to run a test cycle to make sure everything’s been repaired properly and you’re back in business.