As I am ducking my head under the range exhaust vent during a home inspection, he asks what would I be looking at under there. I explain to him that I am looking at the filter set up. There are filters there? Oh, you do not cook much do you. I explain to him why the filter are needed, and how to care for them. We then go over some of the other filters in the home. I realized that I should share facts about filters here, when I was asked about them again recently on another job and at a party.
You have filters at your air intakes for the air conditioning system, the kitchen for your cooking area, and in your bathroom exhaust fans (sometimes). For any of these pieces of equipment to work well, the filters need to be clean. Most homeowners have disposable filters on their air conditioning return vent, but I suggest having a washable one installed. For your air conditioning system to work, you need air coming into the system. This air flows through the filter, which catches the debris. The debris clogs up the filter, which makes the system work harder. For energy efficiency, your filter should always be clean. That is why most utility companies now encourage you to change out your filter each month. If you consider that buying twelve filters is about the same price as buying a decent washable one, which can be used for many years, you will be saving money in the long run. Most washable filters for air conditioning systems just need to be hosed down in the garden. Kitchen exhaust filters are a bit different. When you cook, bits of grease will be in the air. These are caught in the exhaust filter, when it is on. If enough grease collects in the filter, you could have this fall into your food while cooking, but it could also pose a fire hazard. This filter needs to be cleaned with soap and water like your pots and pans. You may be able to place this in the dishwasher, but I would look at your filter first. If it looks a little flimsy, then it will not be able to withstand a wash in that appliance. It takes awhile for these kitchen filters to become really dirty, but I clean mine once a month.
Bathroom exhaust fans are meant to rid that room of water vapor not odors. Consumers think that it is meant to rid these rooms of the disagreeable odors form the toilet, but water vapor, steam, from a shower or bath can do a nice bit of damage to your walls. These units do not really need a filter, but I have seen some that have a filter in them. Usually, these are just pieces of foam. You should rinse them out when they are dirty, but there does not need to be any monthly schedule, because these filters are not in constant use.