When it comes to flexible drain pipe fittings there isn't a magic number that can tell you when to replace them, but there are a few guidelines that you can follow to determine for yourself when they need to be changed. Here are a few things that you will want to consider when thinking about your own drain pipe fittings.
Wear and Tear
The first thing that you want to look at is the condition of the pipe fitting. If you see that it is dirty, you can remove it and clean it off for further inspection. Then you will be able to see whether this is something that can be fixed with a little bit of cleaner or if it needs to be replaced because of rust or corrosion. Many times you will get normal wear and tear from the fixtures or if they are wet then they can easily rust quickly. If you see that the damage done requires more than a cleaning, you can replace them with new fittings. The same goes for when they completely break off. This doesn't happen too often, however, it is possible from all of the wear and tear that goes on over the years especially if you have had a lot of drain problems and they have been removed a lot.
Pipe replacement is another time when you should consider updating the fittings. The reason that some professionals recommend replacing the fittings when getting new pipes even if it is the same material and size is because you will be able to keep in mind and remember how long you have had them and won't have to replace them separately. Then you can update everyone at once and not have to worry about one rusting before the other and so on.
You do want to make sure that if you are moving into a new home that everything is up to code with your village's building department. This can be done when you move in as well as every few years. Typically, you will not have a problem after the initial check but it does not hurt to make sure.
While it does not happen very often, there have been recalls on the fittings or drain pipes so if this were to happen you would want to make sure that you change the fittings to make sure that they are up to date and that they work properly.
Again, there isn't really a set time that you will need to replace your drain pipe fittings, however, keeping an eye out to make sure that all of the above things are checked and in line is the best method to making sure that your drain and fittings stay secure. Making sure that they are up to date now as well as that they are maintained well can help to prevent a lot of problems with the plumbing in the future.