The Worcester 4000/1000/8000 Filling Loop Key is a genuine part suitable for use with corded electric, gas/petrol, and hydronic (hot water) systems. Made from brass and metal, this compact storage tank water heater features a side water connection and is designed for wall mounting indoors. With a power source of less than 1000W, this key is a reliable solution for maintaining your heating system efficiently. The black colour and compact design make it a versatile option for any home heating setup.
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