1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the Moen Brass Commercial 1/2-Inch PEX Posi-Temp Bathroom Shower Valve, Model 8373HD. This valve is engineered for reliable and long-lasting performance in both residential and commercial environments. It features a heavy-duty brass valve body and a single-handle tub and shower cartridge designed to withstand daily use. The integrated Posi-Temp® pressure-balancing technology ensures consistent water temperature by automatically adjusting for pressure fluctuations, thereby enhancing user comfort and safety. The valve is equipped with 1/2-inch crimp ring PEX connections for compatibility with modern plumbing systems and simplified installation, and its four-port design allows for flexible tub and shower configurations. This durable valve has undergone rigorous testing to exceed industry standards for real-world wear and tear, ensuring it performs like new for decades.
Figure 1: Moen Brass Commercial 1/2-Inch PEX Posi-Temp Bathroom Shower Valve (Model 8373HD)
2. Key Features
- Posi-Temp Pressure-Balancing Control Valve: Helps maintain consistent water temperature in the shower, preventing sudden temperature changes.
- Heavy-Duty Brass Single-Handle Cartridge: Ensures durability and reliable operation for both tub and shower functions.
- 1/2-Inch Crimp Ring PEX Connection Type: Designed for compatibility with PEX plumbing systems, facilitating easier installation.
- Four-Port Design: Offers versatility for various tub and shower configurations.
- Durable Construction: Tested beyond industry standards to withstand extensive use, ensuring long-term performance.
3. Setup and Installation
Proper installation is crucial for the optimal performance and longevity of your Moen shower valve. It is recommended that installation be performed by a qualified plumber or a professional with experience in PEX plumbing systems.
3.1 Pre-Installation Checklist
- Ensure all necessary tools and materials are available (PEX crimping tool, PEX tubing, fittings, etc.).
- Verify that the water supply to the installation area is turned off.
- Confirm that the rough-in dimensions meet the requirements for the Moen 8373HD valve.
3.2 Installation Steps (Overview)
- Mount the valve body securely to the framing using appropriate fasteners. Ensure the "UP" marking on the valve is oriented correctly.
- Connect the hot and cold water supply lines to the designated 1/2-inch PEX inlets on the valve using crimp rings and a PEX crimping tool.
- Connect the showerhead and/or tub spout lines to the corresponding 1/2-inch PEX outlets. The four-port design allows for flexible routing.
- Perform a leak test by slowly turning on the water supply and inspecting all connections.
- Install the trim kit (sold separately) according to its specific instructions, ensuring proper alignment and sealing.
Figure 2: Moen 8373HD Valve with 1/2-inch PEX connections for hot, cold, shower, and tub lines.
3.3 Installation Video
Video 1: Product Overview and Installation Guidance for Moen Brass Shower Valve. This video provides a visual guide to the features and installation process of the Moen Brass Shower Valve, highlighting key components and connection types.
4. Operation
The Moen 8373HD Posi-Temp valve is designed for simple and intuitive operation, providing consistent water temperature.
4.1 Temperature Control
- Rotate the single handle to adjust the water temperature. Turning the handle counter-clockwise typically increases hot water, while clockwise rotation increases cold water.
- The Posi-Temp feature automatically maintains your selected temperature, even if water pressure fluctuates elsewhere in your home.
4.2 Flow Control
- The handle also controls the water flow. Pulling the handle out or rotating it to a specific position will turn the water on and off.
5. Maintenance
Regular maintenance helps ensure the continued optimal performance of your Moen shower valve.
- Cleaning: Clean the visible parts of the valve and trim with a soft cloth and mild soap. Avoid abrasive cleaners or harsh chemicals that can damage the finish.
- Cartridge Inspection: If you notice a decrease in water flow, inconsistent temperature, or leaks, the cartridge may need inspection or replacement. Consult a qualified plumber for cartridge servicing.
- Water Shut-off: For any maintenance requiring water shut-off, locate the main water supply valve for your home or the individual shut-off valves if installed on the supply lines to the shower valve.
6. Troubleshooting
This section addresses common issues you might encounter with your Moen Posi-Temp shower valve.
| Problem | Possible Cause | Solution |
|---|---|---|
| Inconsistent Water Temperature | Faulty Posi-Temp cartridge or debris in the valve. | Inspect or replace the cartridge. Flush the valve to remove debris. |
| Low Water Flow | Clogged showerhead, debris in the valve, or partially closed shut-off valves. | Clean showerhead. Inspect and clean valve. Ensure shut-off valves are fully open. |
| Leaking from Handle/Trim | Worn O-rings or seals in the cartridge. | Replace the cartridge. Ensure trim is properly seated and tightened. |
| Water Not Shutting Off Completely | Worn cartridge. | Replace the cartridge. |
If these troubleshooting steps do not resolve the issue, please contact Moen customer support or a qualified plumbing professional.
7. Product Specifications
- Model Number: 8373HD
- Brand: Moen
- Material: Brass
- Inlet Connection Type: Cross Linked Polyethylene (PEX)
- Outlet Connection Type: PEX
- Outlet Connection Size: 0.5 Inches
- Number of Ports: 4
- Valve Type: Cartridge
- Item Dimensions (L x W x H): 2.13 x 4.31 x 4.5 inches
- GTIN (Global Trade Identification Number): 026508228500
- UPC: 026508228500
8. Warranty and Support
The Moen Brass Commercial 1/2-Inch PEX Posi-Temp Bathroom Shower Valve (Model 8373HD) is backed by Moen's Five-Year Limited Warranty. This warranty covers defects in material and manufacturing for a period of five years from the date of purchase. For detailed warranty terms and conditions, please refer to the official Moen warranty documentation included with your product or visit the official Moen website.
8.1 Customer Support
For technical assistance, replacement parts, or warranty claims, please contact Moen customer service. You can find contact information on the official Moen website or through the provided documentation.
Visit the official Moen Store on Amazon for more products and information.
