Why is My Air Conditioner Rusting? - American Air & Heat
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    Why is My Air Conditioner Rusting?


  • Why is My Air Conditioner Rusting?

    May 13, 2011

    Electrolysis: Whenever different metals are placed in a conductive liquid you create a battery. If you connect pieces of metal together, current will flow. The current will be removing metal from one of the metal pieces… electrolysis. If the piece of metal is zinc in your flashlight battery it is good but if one is your air conditioning unit it is bad.

    Galvanic Scale:

    1. Zinc
    2. Aluminum
    3. Galvanized Steel
    4. Cadmium
    5. Mild Steel, Wrought Iron
    6. Cast Iron
    7. Lead- Tin Solder
    8. Lead
    9. Brass, Bronze
    10. Copper
    11. Stainless Steel that has been chemically cleaned

    Metals at beginning will corrode faster than metals at the end of the scale.

    Avoid contact between metals that are farther apart on the scale. All refrigerant lines are made of copper, when you have an aluminum coil you have dissimilar metals contacting each other.

    For years all air conditioning manufacturers have been plagued with the expensive problem of condensing coils corroding. When this happens it results in unsightly and ineffective coils and resulting in higher electric bills. Generally condensing coils are cleaned twice a year. Corrosion is a continuous process and will degrade them between cleanings. Cleaning the coils more often shortens the life of the fins and results in the need of replacement. Coil Coatings have been used but often require recoating during the life of the equipment. The condensing unit is made of Copper, Steel and Aluminum. The salt air acts as an Electrolyte. Therefore the Electrolysis (Galvanic Corrosion) begins damaging your air conditioning system as soon as you turn it on. The Electrolysis will only damage one metal and that is the softest or weakest metal on the system.

    The Corrosion Grenade is 100% Zinc and protects all metals on your air conditioning system because it is the softest or weakest metal on the Galvanic Scale and protects the metals acting as a sacrificial anode. As soon as you have attached the Corrosion Grenade you have introduced a softer metal than any other on the Galvanic Scale. This increases the life of your system and helps maintain the efficiency. Water heaters have used sacrificial anodes for years as well as boat engines used in saltwater.

    To learn more about the Corrosion Grenade™ Contact American Air and Heat at 800-715-7503.