Magnesium anode 5/4" 33x450 - OKC300 (before 2018), OKC200/250/300/400 (from 2018) 83.30.29

Cathodic protection of enamelled tanks

The magnesium anode is a key element of the anti-corrosion protection system in capacity domestic hot water heaters made of steel coated with an internal layer of ceramic enamel. Its operation is based on utilizing the difference in electrochemical potentials between the tank material and the magnesium anode, which effectively prevents electrochemical corrosion.

In the aqueous environment of heating installations, corrosive micro-cells naturally form due to contact between different installation materials such as steel, copper, or brass. The magnesium anode functions as a "sacrificial" element - thanks to its high chemical reactivity, it gives up electrons to the protected metals, completely eliminating the oxidation process of the tank surface.

The industrial enamelling process ensures coverage of over 99.9% of the surface in accordance with the DIN 4753 part 3 standard; however, unavoidable microscopic pores leave small areas exposed to direct contact with the corrosive environment. It is precisely these spots that are protected by the actively functioning magnesium anode.

Technical parameters and compatibility

Model 83.30.29 is characterized by a 5/4 inch thread, a diameter of 33mm, and a length of 450mm, making it an ideal solution for a wide range of Hewalex brand heaters. Selecting the appropriate anode requires considering both the thread dimensions and the tank volume to ensure an optimal protective surface.

Model compatibility

• OKC300 - all units manufactured before 2018
• OKC200, OKC250, OKC300, OKC400 - all units manufactured from 2018 onwards

The anode is mounted as standard equipment for every enamelled domestic hot water tank, constituting an integral structural element of the cathodic protection system.

Service and operation

The rate of magnesium anode consumption is directly dependent on the parameters of the domestic water - particularly its hardness and chemical aggressiveness towards non-ferrous metals.

Recommended service schedule

• Anode condition check at least once a year
• Mandatory replacement when wear exceeds 2/3 of the initial volume
• Maximum replacement interval - 24 months

Regular anode replacement is a fundamental condition for maintaining the heater manufacturer's warranty and preserving the full efficiency of the cathodic protection system throughout the entire service life of the heating device.

In practice, it is recommended to check the condition every 12-18 months, and in the event of significant corrosion or wear being detected - immediate replacement to ensure continuous protection against the corrosive degradation of the metal elements of the water installation.