TUTTNAUER AIR OUTLET VALVE

The Air Outlet Valve is an electronic solenoid valve mounted on the rear of the Water Reservoir. This Air Outlet Valve has several different functions.

• During the Filling phase, the Air Outlet Valve is open to allow for the smooth flow of water from the Reservoir. Without this valve, water flowing into a hot Chamber would immediately produce steam and pressure. The pressure would push on the water, stopping it from entering the Chamber. This would result in an incomplete fill and the inability of the autoclave to complete a cycle.
• During the Heat up phase, the Air Outlet Valve is open to assist the Air Jet in removing any air from inside the Chamber. Air trapped inside the Chamber will cause cold spots as well as a general difficulty in reaching the proper sterilization temperature. Once the temperature reaches 195o F, the Air Outlet Valve closes and any remaining air finishes exiting through the Air Jet.
• During the Sterilization phase, the Air Outlet Valve remains closed, unless the pressure rises above 34 psi. In this case, the Air Outlet Valve will open for one second to emit a short blast of steam to stabilize the Chamber pressure.
• The Air Outlet Valve will open at the end of the Exhaust phase to release the final 3 pounds of steam pressure.
• During the Drying phase, the Air Outlet Valve is open to allow the heat and steam to escape from the drying packs.

Troubleshooting The Air Outlet Valve

Air Outlet Blows Off Steam During The Sterilization Cycle

Air Outlet Stays Open All The Time

On The Ajun3 Board

1. Check between TP14 and TP1; the reading should be between 3.5 and 5 volts DC when the valve is off and 0 to 1 volt when the valve is on.
2. If TP14 is showing 0 to 1 volt constantly, this indicates a control problem .
3. If TP14 is between 3.5 and 5 volts and the valve is open, check for a ground short in the black wire going from the solenoid to the Electronic Box.

On The Air Valve Assembly

1. Remove the Solenoid Coil and check across the terminals for a short 
2. Take apart the Plunger Assembly and clean any debris that may be stopping the Plunger from sliding back and forth 
3. Check the housing of the Plunger for any nicks or distortions that can cause the Plunger to become stuck 

Air Outlet Opens At The Wrong Time

If the unit has a defective LM34 temperature sensor (not a PT100 or LM34 replacement kit) this can cause the Air Outlet Valve to open at the wrong time. A good indication of a bad temperature sensor is if the display changes abruptly either by itself or when the wire is touched

On The Ajun3 Board

1. Check between TP14 and TP1 for the correct signal voltage, either a 0 to 1 volt DC reading if the valve is supposed to be open or 3.5 to 5 volts if the valve should be closed. If TP14 shows an incorrect signal, this would indicate a control problem 

On The Air Valve Assembly

1. Check for a shorted black wire going to the Solenoid Coil.
2. Remove the Solenoid Coil and check for a short in the Solenoid Coil 
3. Remove the connection box from the Solenoid Coil and check that the connectors are in place and making good contact with the terminals on the Solenoid Coil