384 Door Open error

What is the name of the manufacturer and model of the equipment you are working on? 

Mdimark Ritter M9-020. Should have included that!

One of these companies may be able to assist:

iMed 

Meriam 

RPI  

I found on a few there is a metal plate that needs to be bent slighly to push the door a little make sure the door swtich is fully engaged. Not sure if that's the issue, but worth a look and check. 

Make sure the pop-off valve is working!

it's true that the spring arm does act as an actvator for the door switch - be sure the the right angle bend at the very end of the arm is not cracked or damaged.  This problem can also show up when the door closing assembly located on the door under the plastic panel loosens up and the door pins can shift around and fall slightly off the srping arm - be sure the hardawre is all tight and that the brackets have not been bent.  

there is a microswitch in the door bracket. that could be faulty, you can ohm it out via the connector on the pcb. if it checks out, figure out at what point in the cycle your alarm comes up, watch the door to see if you notice any movement. If you do you'll need to adjust one of several components.  If both of these check out, bypass the door switch by placing a paperclip or cable with alligator clips on the 2 contacts for the door switch at the pcb and run a cycle, if it comes up again, you'll need to replace the pcb. If you're in NY, NJ or CT we can schedule a tech to inspect and repair your machine, or you can ship it to us. 

Look up Sterilizer Autoclave Solutions, they specialize on midmarks.