De Dietrich 300009074 3 pin connector A pump/SV

This 3-pin connector is a component of the low-voltage or mains wiring harness in a boiler or burner control system. Parts of this type are used to connect a pump or a solenoid valve (SV) to the control board. The connection relies on the pin count, pitch, and keying of the connector rather than its function; a 3-pin connector of this series is matched to the corresponding socket on the control board or the appliance harness. When selecting a replacement, confirm the connector series, pin orientation, and the crimp or solder terminal type. The conductor cross-section and insulation temperature class must also match the original cable to avoid overheating or poor contact. In a boiler system, the pump is typically energised by the control board to circulate water on a heat demand, while a solenoid valve opens or closes fuel supply. A faulty connector at either point can cause intermittent operation, failure to start, or a lockout. Because poor contact in a connector can reproduce almost any electrical fault symptom, such connectors are a routine suspect during fault finding. Always inspect the pins and sockets for corrosion, bent contacts, or loose retention before replacing a board or a pump. This specific article is listed under plugs and connectors; use the manufacturer codes 300009074 and 336.640.003 when ordering.