Understanding An Old School Fuse Box - YouTube Click to view on Bing6:57Here's a quick review of how to use a fuse box (with the screw-in fuses) safely and some discussion about what to look out for in an old house.Author: enduringcharmViews: 220K How To Change Fuses in an Old Home Panel - YouTube Click to view on Bing4:00How To Change Fuses in an Old Home Panel Blue Collar DIY. 20 amp time delay fuse - https: How to ground an old style electrical outlet box. 1 - Duration:Author: Blue Collar DIYViews: 44K A Guide to Screw-In Fuses and How They Work For example, it stops a person from putting a 20-amp fuse in a 15-amp circuit, a potentially serious mistake. This condition is called "over-fusing" and can result in the fuse failing to blow before the circuit wiring overheats and potentially catches fire. A 15-amp Type S fits only a 15-amp base adapter.Author: Bob Formisano Buying a new (old) house. It has a fuse box. Questions inside. If you have 14 gauge wiring (standard in older houses), you should only use a 15 amp fuse, but if the fuse keeps burning out people eventually discover that a 20 amp fuse fits just fine & doesn't burn out - but it also allows the wiring to overheat. As long as you stick to 15 amp fuses you won't start any fires.