Introduction
This manual provides essential information for the proper installation, operation, and maintenance of your General Pump 3/8" Pump Thermal Protector, model #100557. This component is designed to safeguard your pump from damage caused by excessive heat accumulation during bypass mode operation.
Product Overview
The thermal protector functions as a thermal relief valve. When the pump operates in bypass mode, water recirculating within the pump can rapidly increase in temperature. This device senses the rise in temperature and automatically opens to discharge a small amount of heated fluid, allowing cooler water to enter the system and cool the pump. Once the pressure washer gun is discharged, the cooler water causes the valve to close, maintaining optimal operating conditions.
This image displays the General Pump 3/8 inch Thermal Protector, model #100557. It features a brass body with a 3/8 inch NPT threaded inlet on one end and a black plastic thermal sensing element with a 1/4 inch 90-degree hose barb on the other. The hexagonal brass body allows for easy installation with a wrench.
Setup and Installation
The General Pump Thermal Protector is designed for straightforward installation. It can be mounted in various locations within your pump system to effectively monitor and regulate temperature.
- Mounting Locations: The protector mounts easily in the pump manifold, the inlet water supply line, or within the bypass loop plumbing.
- Connection: The inlet connection is 3/8" NPT. Ensure proper threading and sealing during installation to prevent leaks.
- Hose Barb: The outlet features a 1/4" 90° hose barb for connecting a discharge line to safely route the released hot water away from the pump and operator.
- Temperature Rating: The relief temperature is set at 145°F (63°C).
Always ensure the pump system is depressurized and cooled before attempting installation or maintenance. Use appropriate thread sealant for NPT connections.
Operating Principles
The thermal protector operates automatically based on water temperature. When the pump is running but the spray gun is closed (bypass mode), water continuously circulates within the pump. This circulation generates friction and heat. If the water temperature reaches approximately 145°F, the thermal protector's internal mechanism activates, opening a small valve. This allows a controlled amount of hot water to exit the system through the hose barb, simultaneously drawing in cooler water from the inlet. This process prevents the pump's internal components from overheating. Once the spray gun is activated, the flow of water through the pump increases, and the temperature typically drops, causing the thermal protector to close and maintain normal operation.
Maintenance
Regular inspection of the thermal protector is recommended to ensure its continued functionality. Check for any signs of leakage around the threads or the hose barb connection. Ensure the discharge hose (if installed) is clear and not obstructed. If the protector is frequently discharging water at temperatures below its rated relief temperature, or if the pump is overheating despite the protector being installed, it may indicate a need for inspection or replacement.
Troubleshooting
- Constant Water Discharge: If the thermal protector is constantly discharging water even when the pump is not in bypass mode or the water is not hot, it may be stuck open or faulty.
- Pump Overheating: If the pump is overheating despite the thermal protector being installed, the protector may be clogged, faulty, or incorrectly installed. Verify the relief temperature and ensure proper water flow.
- Leaks: Check all connections for proper sealing. If the leak is from the body of the protector, replacement may be necessary.
For persistent issues, consult a qualified technician or contact General Pump support.
Specifications
| Inlet Connection | 3/8" NPT |
| Outlet Connection | 1/4" 90° Hose Barb |
| Relief Temperature | 145°F (63°C) |
| Actual Outside Diameter | 0.675" |
| Material | Brass |
| Item Weight | 1.6 ounces |
| Product Dimensions (L x W x H) | 2 x 1 x 1 inches |
| OEM Part Number | 100557 |
| Fit Type | Universal Fit |
Warranty Information
Specific warranty details for the General Pump 3/8" Pump Thermal Protector #100557 are not provided in this manual. For information regarding product warranty, please refer to the documentation included with your purchase or contact General Pump directly.
Support
For technical assistance, replacement parts, or further inquiries regarding your General Pump Thermal Protector, please contact General Pump customer support. Contact information can typically be found on the manufacturer's official website or on your product packaging.
