Sloan A 19 A
The Sloan A 19 A (also cataloged as part number 5301139) is a precision-machined brass relief valve component located at the center of the diaphragm assembly inside Sloan Royal, Regal, and Crown commercial flushometer valves. Operating on hydrodynamic pressure differential principles, the Sloan A 19 A relief valve regulates the exact flow cycle of commercial water closets and urinals. When the flushometer handle is actuated, the plunger tilts the A-19-A valve stem, releasing upper chamber water pressure to initiate flushing. Understanding this component is essential for facility managers and commercial plumbers diagnosing running toilets and water waste.
Function, Hydraulics, and Assembly Integration
Commercial diaphragm flushometers divide incoming water supply into an upper pressure chamber and a lower discharge chamber separated by a flexible synthetic rubber diaphragm. Because the surface area of the diaphragm inside the upper chamber is greater than that of the lower chamber, static line water pressure holds the diaphragm firmly sealed against the main valve seat. The Sloan A 19 A brass relief valve sits directly in the center of the diaphragm, acting as the dynamic mechanical trigger for the entire flushing cycle.
When an occupant operates the exterior chrome handle, an internal handle plunger pushes horizontally against the vertical stem of the Sloan A 19 A valve. Tilting the valve unseats its internal rubber seal, instantly venting the water trapped in the upper chamber through the central relief port down into the toilet bowl. With upper pressure relieved, high-pressure line water in the lower chamber pushes the diaphragm upward, producing a powerful, high-volume flush until water gradually refills the upper chamber through a bypass orifice, re-seating the A-19-A valve.
The table below outlines technical specifications, materials, and compatible Sloan flushometer models for the A-19-A relief valve.
| Specification Field | Technical Data | Operational Function | Plumbing Standard |
|---|---|---|---|
| Manufacturer Part Number | A-19-A (Code No. 5301139) | Primary OEM relief valve assembly | Meets ASSE 1037 performance code |
| Material Construction | Machined commercial brass & elastomer | Resists chloramine and harsh municipal water | Dezincification-resistant brass alloy |
| Valve Compatibility | Sloan Royal, Regal, Crown flushometers | Fits commercial water closet & urinal valves | Standard across 1.0 to 3.5 GPF units |
| Physical Dimensions | 1.75 inch total length, threaded body | Threads directly into center diaphragm core | Precision machine threading |
| Associated Repair Kit | Sloan A-38-A, A-41-A diaphragm kits | Core replacement piece in drop-in kits | Packaged with molded synthetic diaphragm |
The brass construction of genuine Sloan A-19-A valves resists chemical degradation from chloramines and hard water lime scale.
Diagnosing Continuous Flushing and Failure Modes
The most frequent commercial flushometer malfunction is a valve that runs continuously, wasting hundreds of gallons of treated municipal water. In a significant percentage of cases, this failure originates directly at the Sloan A 19 A relief valve. If mineral sediment, calcium flakes, or pipe scale lodge beneath the relief valve seat, the valve cannot reseat vertically. Consequently, upper chamber pressure cannot rebuild, and the main diaphragm remains lifted in an open, non-stop flushing state.
Physical wear of the valve stem is another common issue in high-traffic facilities such as airports, schools, and arenas. After tens of thousands of cycles, the brass stem can develop metal burrs or bending caused by forceful handle kicking. Furthermore, the small rubber relief valve seat disk can harden, tear, or succumb to chemical oxidation. In modern maintenance protocols, commercial plumbers replace the entire drop-in diaphragm assembly—which contains a pre-installed factory-torqued A-19-A relief valve—to guarantee consistent flush volume and prevent future leaks.
The table below provides a diagnostic troubleshooting matrix for flushometer symptoms involving the Sloan A-19-A relief valve.
| Flushometer Symptom | Underlying Valve Defect | Inspection Finding | Corrective Plumbing Action |
|---|---|---|---|
| Continuous Run (No Shutoff) | A-19-A valve unseated or debris fouled | Debris trapped under brass valve head | Disassemble, flush body, replace diaphragm/valve |
| Short Flush (Insufficient Water) | A-19-A stem bent or bypass enlarged | Premature upper chamber repressurization | Install new OEM calibrated diaphragm kit |
| Handle Leaking During Flush | Plunger seal worn or valve stem sticky | Water backing into handle socket | Rebuild handle assembly with B-50-A kit |
| Excessive Flush Volume (Overspray) | Relief valve remaining open too long | Sediment partially blocking bypass orifice | Clean bypass hole, replace relief valve assembly |
| Chattering / Water Hammer Noise | Loose relief valve or worn diaphragm guide | Vibration of internal valve components | Tighten inside cover, replace worn diaphragm unit |
Shutting off the water supply stop valve before removing the flushometer top cap prevents high-pressure flooding in commercial restrooms.
How to Replace a Sloan A 19 A Relief Valve in 4 Steps
Follow this commercial plumbing procedure to replace a damaged Sloan A-19-A relief valve inside a flushometer.
Shut Off Supply at Control Stop
Use a flat-blade screwdriver to turn the control stop valve screw clockwise until the water supply to the flushometer is completely shut off.
Remove Outer and Inner Valve Caps
Unscrew the chrome outer cover using a smooth-jaw spud wrench to prevent marring the finish, then lift out the molded plastic inner cover.
Extract Diaphragm and Inspect A-19-A Valve
Lift the diaphragm assembly out of the valve body, unscrew the damaged brass A-19-A relief valve from the center, and clear any sediment in the chamber.
Install Replacement Valve and Reassemble
Thread the new genuine Sloan A-19-A valve into the diaphragm core, reseat the assembly into the valve body, replace covers, and adjust the control stop.
Frequently Asked Questions (8 Questions Answered)
Q1: What is the function of the Sloan A 19 A valve?
The Sloan A 19 A is a brass relief valve that vents water pressure from the upper chamber of a flushometer when the handle is pushed, allowing the valve to open and flush.
Q2: What part number corresponds to the Sloan A 19 A?
The official Sloan catalog code number for the A-19-A relief valve is 5301139.
Q3: Why does a toilet with a Sloan valve keep running?
A continuously running Sloan valve is usually caused by sediment trapping the A-19-A relief valve open, a clogged diaphragm bypass hole, or a deteriorated rubber diaphragm.
Q4: Is the A-19-A relief valve sold separately or with the diaphragm?
While the A-19-A brass relief valve can be purchased individually, it is most commonly replaced as part of a complete pre-assembled Sloan diaphragm rebuild kit.
Q5: Can you use an A-19-A valve in both water closets and urinals?
Yes, the A-19-A relief valve is universal across standard commercial Sloan flushometers, though the diaphragm bypass hole determines the specific flush volume.
Q6: What tools are needed to service a Sloan flushometer valve?
You need a flat-blade screwdriver for the control stop and a smooth-jaw wrench (spud wrench) to avoid damaging the chrome outer cover.
Q7: What is the difference between Sloan Royal and Regal valves?
Royal valves use a non-hold-open dual-filtered fixed bypass diaphragm, while older Regal valves use an adjustable brass bypass assembly, though both use compatible relief valves.
Q8: Can hard water damage the Sloan A-19-A valve?
Yes, heavy lime scale and mineral buildup can coat the brass stem and rubber seating disc, preventing the valve from making a watertight seal.
Final Thoughts & Key Takeaways
In conclusion, understanding sloan a 19 a provides essential clarity, practical strategies, and actionable advice. By incorporating these foundational insights, adhering to verified safety guidelines, and following structured best practices, you ensure reliable, long-term outcomes while preventing common mistakes. Stay informed, consult certified professionals when needed, and maintain consistent quality care.