De Dietrich 95325102 unipolar momentary switch

This is a De Dietrich unipolar momentary switch, listed under the Plugs and connectors category. The manufacturer codes are 95325102 and 336.559.003. A switch of this type is a normally open, spring-return push button that closes the circuit only while it is pressed. In a burner or boiler panel, such switches are commonly used for manual reset after a lockout, for test functions, or to initiate a short manual action like a forced start. The switch has a single pole and does not latch—it returns to the off position as soon as the button is released. When selecting a replacement for a unipolar momentary switch, the key parameters are the rated voltage and current, the physical mounting dimensions (panel cut-out size and depth), and the type of terminals (e.g., spade, screw, or solder). Because the switch sits in the control circuit, typically carrying low-voltage signals from the burner control or the power supply to a relay, the electrical ratings must be equal or greater than the original. The mechanical feel and actuation force are also relevant if the switch is used as a frequent reset button. Pay attention to the terminal configuration: a unipolar switch has two connections, and the switch must be wired in series with the load it controls. If the original switch had a specific colour or internal illumination, verify those details. Poor contact in a switch can mimic a control board fault, so always confirm that the new switch makes a clean, solid connection when pressed. This article carries the De Dietrich brand, but the generic performance criteria apply.