That is a good question. Well here is one answer. To be on the safe side two times a year. That is the recommendation of all fire departments. I do it ones a year some time and it is OK but I should do it twice a year. Please do not wait until they start beeping it will drive you crazy before you get them changed because they will most always start beeping at night. It must be some kind of law or something! If you are not able to change you batteries give us a call. We can do it for you. The batteries will cost you $3 each if you buy them from us. We use Kodak made in the USA batteries mostly. We do have a $55 minimum charge to come out and do this so if you have other people around you can split the cost! Say you have four neighbors and you all need batteries replaced and it takes use one hour or less to install everyone's batteries. Our minimum charge plus the batteries would be divided between you like this. You get 15 minutes each for us to install the batteries and get to the next house but if you go over it will be $.50 a minute.

That is a good question. Well here is one answer. To be on the safe side two times a year. That is the recommendation of all fire departments. I do it ones a year some time and it is OK but I should do it twice a year. Please do not wait until they start beeping it will drive you crazy before you get them changed because they will most always start beeping at night. It must be some kind of law or something! If you are not able to change you batteries give us a call. We can do it for you. The batteries will cost you $3 each if you buy them from us. We use Kodak made in the USA batteries mostly. We do have a $55 minimum charge to come out and do this so if you have other people around you can split the cost! Say you have four neighbors and you all need batteries replaced and it takes use one hour or less to install everyone's batteries. Our minimum charge plus the batteries would be divided between you like this. You get 15 minutes each for us to install the batteries and get to the next house but if you go over it will be $.50 a minute.