Midmark M9/M11 Error Code C326 Leave a comment

In this article, we’re going to explain one of the many error codes that can affect your Midmark M9/Midmark M11 autoclave. This article will focus specifically on error code C326. We’ll tell you about the problem, what displays when the error occurs, its possible causes, and the course of action to take to resolve said error.

 

However if you’re more of a visual learner we have a video on this error code available here. 

And if you just want to talk to someone, call our Free Tech Support at 704-966-1650 Option 3.

 

Display/Symptom

C326: DOOR MODE DOOR CLOSED

OPEN DOOR

Causes, Checks and Actions

Possible Cause 1: Door Spring Missing/Damaged

• Check 1: If the door motor releases the latch, but the door remains closed. Inspect door spring for damage.
• Check 2: Verify if door is at the vented position. (Push in on door with out lifting handle)
• Check 3: Verify the QTY of door springs. (M11- QTY 2, M9-QTY 1)
• Action: Replace door springs.

The M9/M11 Door Spring can be bought here. 

 

• Check: Verify door springs are at a 45 degree angle.
• Action: Place door spring at a 45 degree angle.

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Possible Cause 2: Door/Dam gaskets

• Check A: Inspect door / dam gaskets for proper installation and any signs of sticking.
• Action A: Install door / dam gaskets properly.

M9 Door/Dam gasket Kit available here.

M11 Door/Dam gasket Kit available here.

• Check B: If new gasket, check if wire ring in gasket is preventing gasket from fully being seated.
• Action B: Temporarily remove wire ring. Re-install wire ring after gasket is fully seated.

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M9 Tray and rack Kit available here.

M11 Tray and rack Kit available here.

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• Check: Inspect latch mechanism for wear / damage.
• Action: Replace worn / damaged components.

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Possible Cause 5: Door motor system / latch “hanging up”

• Check: Remove the door cover and RH side panel. With the door closed, run the ‘Door Open Test’. Watch for any mechanical issues that may prevent the door from opening. Refer to: Service Diagnostics (I/O Test)
• Action: Replace worn / damaged components.

Midmark Door Motor is available here. 

 

• Check: Verify door motor is angled as close to PC board as possible.
• Action: Adjust door motor angle.

 

• Check: Check if the connecting rod is installed in the proper location on the door motor cam. (9 for M9, 11 for M11)
• Action: Install connecting rod in the proper 9 or 11 location on the door motor cam.

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Possible Cause 6: Door Motor Defective

• Check: Remove the door cover and RH side panel. With the door closed, run the ‘Door Open Test’. Watch for any mechanical issues that may prevent the door from opening. Refer to: Service Diagnostics (I/O Test)
• Action: Replace door motor.

Midmark Door Motor is available here. 

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Possible Cause 7: Door hinge binding.

• Check 1: Check for binding or build up of debris in the door hinges.
• Action 1: Clean debris from hinges.

 

• Check 2: If debris cannot be cleaned from hinges to remove binding
• Action 2: Send unit to Midmark for factory Repair and Return.

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Possible Cause 8: Door Switch/PC Board malfunctioning.

Note: Test switch with the door OPEN and Closed. 

 

• Check 1: Perform: Door Switch Continuity Test. With door closed, disconnect door switch wires from J1 & J2 of Main PC board. Place meter probes on door switch wires. If Continuity is not present replace door switch. Refer to: Door Switch Continuity Test
• Action 1: Replace door switch.

Midmark Door Switch available here. 

• Check 2: Check supply voltage from PC board. (Line voltage 120 or 230 VAC) Refer to: Door Switch Supply Voltage Test
• Action 2: Replace main PC board.

M9 PC Board OEM available here

M11 PC Board OEM available here

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 Possible Cause 9: Door switch activation tab obstructed.

• Check: Check for full movement of activation tab.
• Action: Remove any obstruction.

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 Possible Cause 10: Residual pressure in chamber. 

• Check: Check for chamber pressure when door motor is energized.
• Action: Clear any restriction that could prevent chamber pressure from reaching the pressure transducer on PC board.

 

• Check: Check the load size. (Refer to User Guide) Verify that nothing is touching or crowding the temperature sensor.
• Action: Reduce load size.

 

• Check: If pressure is above 0.72 psi (5 kPa), check for blockage in the pressure sensor tubing between the PC board and the chamber.
• Action: Clear blockage / replace pressure transducer tubing.

 

• Check: Check if chamber filter is clogged.
• Action: Clean / Replace filter. (Clean with Speed-Clean and brush)

Chamber filter is available to buy here. 

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As always if you have any questions about this process or anything else please feel free to contact us and take advantage of our “FREE TECH SUPPORT.”

We also offer FREE VIRTUAL TECH SUPPORT to “See and Talk” with a “Real Time Live Technician” for any problems you may be in need of help with.

You can also use our “FREE MAINTENANCE PROGRAM”. Take the guesswork and worrying about what unit is due for maintenance and which maintenance cycle it is time for. We will keep track of all your autoclaves and let you know when it’s time for anything.

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The Midmark M9 autoclave is available here. 

We also have the Midmark M11 autoclave here.