Heating, Air Conditioning, Fridge, HVAC/Buried Propane Tank Lifetime


I rent from my gas company a 500 gallon LPG storage tank that has been buried under foundation planting for over 15 years. I asked them about the lifetime of the tank, and they offered to send someone out to check the “cathodic protection”. Although of somewhat technical inclination, I have no idea what they are talking about. Can you explain?


Cathodic protection is a procedure used to protect an object from corrosion by making it a cathode. To make a tank a cathode, you have to attach an anode to it. Both have to be in an electrolyte such as earth or water. To protect a propane tank, you would attach an anode consisting of a 17-pound bar of magnesium metal packed inside a cloth bag containing 28 pounds of conductivewww.midwaygas.com earth backfill with a wire that is attached to the magnesium and to the tank. The magnesium metal is a source of electrons for the iron atoms and it is from where D.C. current originates. As long as enough electrons flow from the magnesium through the wire and the connections to the tank, the tank will not corrode. At the same time, a small amount of direct current flows from the magnesium metal, through the earth to the tank. The current is less than one amp.

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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