If they malfunction or collapse therefore you have no notion of wrong and the way to fix them, you skill is work with an appliance service which can be found in your town. Getting a professional appliance repairman might not exactly totally help you save from pocket money but least it could actually help you save a serious amounts of save you from more trouble.
Though, if you are some of those people who find themselves
knowledgeable about equipment circuits or whatever it really is inside
black box, you may want to make use of your screwdriver and open it up.
All you need to do is trust a manual for troubleshooting your appliance.