The filters make a popping or crackling sound or spark when I plug them in. Is there something wrong?

Is there a large whole-house filter that can install by the breaker panel, so that I don't have to use individual small filters throughout the house?

I install a filter, but the reading doesn't go down to 30 or below. What can I do?

My meter displays a 1 or a 0 or doesn't display anything when I plug it in.

My filters make a buzzing or humming sound. Are they defective?

When I install a filter in my kitchen, the reading in the outlet goes down, but the reading in another outlet goes up. Why is this?

Do your filters work with Europe and other 220/240 volt countries?

Do I need a Stetzerizer Filter plugged into an outlet with no power?

How long do Stetzerizer Filters last? They should last a lifetime!