Air Valve Assembly 04-2000-07 for Wilden 1.5 Inch Diaphragm Pump – Replacement for P400 Metal AODD Pump | OEM Spec

Key features

• Exact replacement for Wilden part #04-2000-07 – this air valve assembly is engineered specifically for 1.5 inch (1½") Wilden P400 metal diaphragm pumps, delivering precise air distribution to ensure smooth, stall-free operation in continuous industrial service.
• Fixes critical pump failures: pump won’t start, erratic cycling, excessive exhaust icing, low flow output, or complete loss of suction – common symptoms caused by spool seizure, internal leakage, or moisture corrosion in original or worn 04-2000-07 valves.
• Designed for direct compatibility with P400-series pumps: fits all standard 1.5" metal-bodied models including P4/AAAPP, P4/SSTPP, P4/SSAAB, and other bolted-metal configurations used in chemical transfer, paint circulation, and wastewater applications.
• Built to OEM dimensional and performance specs – matches the internal spool geometry, air port timing, and sealing interface of genuine Wilden valves, enabling drop-in installation without system bleeding or controller adjustment.
• Constructed with high-grade materials – features a corrosion-resistant housing and precision-ground internal components that withstand harsh environments, including exposure to solvents, acids, and high-humidity conditions typical in industrial settings.
• Always confirm your pump size and part number: verify your machine uses a 1.5 inch Wilden P400 pump and that the existing valve is stamped 04-2000-07 (note: “04” prefix = 1.5" platform; do not confuse with 02- / 08- / 15- series for other sizes).

In 1.5 inch Wilden P400 metal diaphragm pumps, the air valve assembly 04-2000-07 acts as the central control unit—sensing pressure differentials and instantly redirecting compressed air to alternate sides of the pump chamber. When this valve degrades due to moisture, particulate contamination, or thermal fatigue, your entire fluid transfer process becomes unreliable. This replacement valve replicates the unbalanced piston design and low-friction sealing dynamics of the original Wilden component. It ensures consistent cycle timing, prevents exhaust icing in cold environments, and maintains stable flow rates—even under variable inlet pressure conditions. Whether you’re a chemical plant operator circulating solvent through a closed-loop system, or a wastewater technician transferring sludge with a P4/SSTPP pump, this OEM-spec 04-2000-07 air valve delivers dependable performance—without the markup of factory-branded parts.

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