Based on your inquiry, the part number **190870** is most commonly associated with a **Pressure Switch** or a specific **Circuit Board component** used in industrial equipment, particularly by manufacturers like **Generac** (for generators) or **Nu-Calgon/York** (for HVAC systems). Below is a breakdown of the technical aspects of this electronic/electromechanical part. --- ### 1. General Specifications If this part refers to the widely used **Pressure Switch** (common in power equipment and HVAC), the technical profile is as follows: | Feature | Specification (Typical) | | :--- | :--- | | **Component Type** | Electromechanical Pressure Switch | | **Function** | Monitors fluid/gas pressure to open or close a circuit | | **Connection Type** | Usually 1/8" NPT or Spade terminals | | **Voltage Rating** | Typically 12V DC (Automotive/Gen) or 24V AC (HVAC) | | **State** | Normally Open (NO) or Normally Closed (NC) | --- ### 2. Common Applications This part number is frequently found in three specific electronic ecosystems: #### A. Generac / Guardian Power Systems In these systems, the 190870 (or 0190870) is often a **Low Oil Pressure Switch**. * **Role:** It acts as a safety sensor. If the oil pressure drops below a safe threshold, the switch changes state, sending a signal to the electronic control board to shut down the engine to prevent permanent damage. #### B. HVAC Control Systems In air conditioning and heating units, this part often functions as a **High/Low Cut-out Switch**. * **Role:** It protects the compressor by breaking the electrical circuit if the refrigerant pressure reaches dangerous levels. #### C. Generic Electronic Components If "190870" refers to a specific passive component (like a capacitor or resistor from an old catalog like Farnell or Mouser): * It is likely a **legacy SKU** for a specific value resistor or a mounting bracket for electronic enclosures. --- ### 3. Troubleshooting & Testing If you are testing this part with a Multimeter, follow these steps: 1. **Continuity Test:** Set your meter to the continuity (beep) setting. 2. **Disconnected State:** Check the terminals while the part is uninstalled. Note if it is "Open" (no beep) or "Closed" (beep). 3. **Active State:** Apply the rated pressure. The switch should "click" and the continuity state should reverse. 4. **Resistance:** If the resistance across the terminals is high (greater than 1-2 ohms) when the switch is closed, the internal contacts are likely carbon-scored and the part needs replacement. ---