Domestic Smoke Alarms

I had 2 burn their micro-pump switches in 12-months of age using different machines. V-hazardous smoke alarm has saved lives first, the second time smelt burning plastic. Worried it might be my fault. Use only cold water, domestic grade soaps, water softener, bleach. In small and airy, with passage of the dryer. pls ideas.

lubricating / changing bearings / moving machine parts

all the best