Ao Smith 100109259 3/4 Inch Tp Relief Valve Water Heater

Product Description

The AO SMITH 100109259 is a genuine OEM temperature and pressure relief valve designed for residential water heater service. The TP valve is a critical safety component that automatically opens to release excess pressure or dangerously high water temperature inside the tank, preventing catastrophic failure. Sized at 3/4 inch, this valve is a direct factory replacement part, supplied in original AO SMITH packaging. Plumbers and water heater service technicians install this valve as part of routine maintenance or emergency repair when an existing TP valve fails to seat, weeps continuously, or does not actuate correctly.

This valve is intended for installation on AO SMITH water heaters, specifically the FCG-40 model. Because fitment is tied to specific model and serial number ranges, this is not a universal or generic replacement. Technicians should verify the unit model and serial number before ordering to confirm this is the correct valve for the application. It is suitable for residential gas water heater installations requiring a 3/4 inch TP relief valve port.

Key Features

• Genuine OEM AO SMITH replacement part — not aftermarket or generic
• 3/4 inch valve connection for standard water heater TP port fitment
• Supplied in original AO SMITH factory packaging
• Designed for the FCG-40 water heater model series
• Critical safety device protecting against over-pressure and over-temperature conditions

Compatibility

Designed as a genuine OEM replacement for the AO SMITH FCG-40 water heater. Fitment is specific to certain model and serial number ranges. Verify the exact model and serial number of the unit before installation to confirm correct application.

Installation Notes

TP relief valve replacement is typically performed by a licensed plumber in accordance with local plumbing codes and the International Plumbing Code (IPC). Always shut off the gas supply and cold water inlet and allow the tank to cool before removing the existing valve. A discharge pipe must be installed on the outlet of the TP valve per code — never cap or plug the discharge port. Do not over-torque the valve into the tank fitting; use thread sealant approved for potable water systems.

Technical Specifications

• Connection Size: 3/4 inch
• Valve Type: Temperature and Pressure (TP) Relief Valve
• Part Classification: Genuine OEM Replacement

Standard Information

• Brand: AO SMITH
• Manufacturer Part Number: 100109259