The title above might be there to get your attention, but the problem is very real -- electric baseboard and in-wall heaters that are unsafe and are known to cause fires. I see lots of them out there and, over time, an inspector kind of learns which ones to be suspicious of. I operate all heaters and try to look inside covers on these heaters, if I think they might be recalled units. There are a number of heaters, from various manufacturers, that have been deemed unsafe. Here in the Pacific Northwest, we see a lot of recalled Cadet fan-assisted in-wall heaters. The thing we inspectors want to make sure of with these units is that, when our clients turn them on, they do not also turn on our clients or burn the house down. Below are photos of a recalled Cadet FX series in-wall heater. To the right is the same unit, with the cover removed. The photo is too small to see the model number, but you can find that in the lower right hand corner of the unit. All of the collected lint and debris, even if this was not a recalled heater, is a safety issue that can cause overheating at any heater. In general, electric heaters should be cleaned monthly but, when that is done, care must be taken that the power is turned off as most of them can deliver 240 volts to the unsuspecting homeowner -- who does not wish to be, and might not survive, being turned on in that manner. Next time you "safely" clean your heaters, you might check inside them for manufacturer and model numbers, then google the numbers. Recalled numbers tend to pop-up quickly in searches. Also you  can get a list of recalls from the consumer products safety commission. An interesting article on Cadet and heater safety, written by a firefighter, is here.