Bg Higg by checked the fuse are you referring to the one under the heater unit?
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Bg Higg by checked the fuse I assume your are referring to the one under the heater unit like shown [https://www.ifixit.com/Guide/ResMed+AirSense+10++Heater+Fuse+Replacement/137047 |on here] Data on the heater is not freely available so I would go ahead and replace the heater on use a bench power supply to see if that could run the heater.