Moisture is the leading cause of hearing aid failure, according to manufacturers. Unfortunately moisture problems are usually not as obvious as droplets visible in the tubing of BTE instruments. Circuitry problems and distortion caused by moisture are actually very difficult to diagnose. However, moisture should not be ruled out when obvious causes such as weak batteries are eliminated or if the problem seems less noticeable in the mornings.

It might be helpful to understand how moisture gets into your hearing aid to begin with. The chief problem is condensation. What causes this condensation? Simply put, warm air holds more moisture and cold air holds less, so moving from a warm environment to a cooler one can cause condensation. This is the same condensation effect seen on a cool bathroom mirror after a hot shower. Similarly, entering an air conditioned building on a warm or humid day will cause condensation, because the cooler inside air cannot hold as much water vapor (that’s why air conditioners put out so much water). Under such conditions—not unusual for most of us in our normal lives—the water vapor condenses as moisture. It is important to understand that in most cases you will not see this condensation, because most problems are caused by moisture molecules, not visible droplets. Even though you can’t see them, you will usually notice their presence, because your hearing aids will not sound as good, you will notice distortion, you might have intermittent failures or faulty switches, or they will simply stop working.