A UV bulb should be replaced every 6 to 12 months to ensure optimum performance and clarity. UV Lamp Sizes (excluding the 2 pins at each end). Zone D - HS, IV41-49, IV50, IV55&56, KA27-28, KW15-17, PA20, PA41-49, PA60-78, PH42-44, ZE, Isle of Man & Channel Islands.
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