Repair Advice for the 1815dn Open Heat Error Message
On these machines like most other Xerox, Dell, and Samsung machines I tend to see errors like the Dell 1815dn Open Heat Error more than I see low or over heat errors. The goods new is that these errors are often easier to resolve than the low heat errors if you have a little technical knowledge and aren’t afraid to take the machine apart a little.
In the picture above I’ve circled in red the thermostats. When the machine over heats these thermostats open to cut off AC power to the unit. When the machine cools down, sometimes these thermostats close and other times they might stay open. When they stay open no AC goes through the circuit and you get the open heat message. In order to clear the message you probably will have to remove the fusing assembly and manually reset the thermostats. Click on the link below to get the instructions on removing the fusing unit then follow the instructions in this article to attempt to reset the thermostats.
Resolving the 1815dn Open Heat Error
Once you have the fusing assembly out. You will need to use a volt meter and check continuity across the thermostats. If you have continuity across the thermostats then check the lamp. If you have no continuity across the thermostats then try the individually. Once you find the one that is open, turn it over so the side facing the hot roller is up. Typically this side as a black leaf spring on it. If you depress the leaf it will bend in. Take a can of air and hold it upside down and give the leaf spring an extreme cold shot of air. This procedure will close the thermostat back up. Test for continuity across the thermostat again. If it test good then install back in the machine and turn back on.