The A and B Recirc to Pump Desiccant Assembly (SKU 236703) is a complete moisture-control and pressure-management solution for spray foam and chemical transfer pump systems. This setup mounts directly into a 3/4-inch drum bung hole and replaces traditional open-air vents with a safe, sealed, and regulated system.

This assembly recirculates back to the pump—not the drum—and includes integrated check valves on both sides for backflow protection and pressure relief. The A-side provides moisture control with a desiccant port, and the B-side manages system pressure through a check-valved return path.

Complete A & B-Side Functionality of the Recirc to Pump Desiccant Assembly

This assembly includes both sides needed for moisture control and pressure regulation:

• A-Side Assembly – SKU 236618
  Designed for moisture control, the A-side features a desiccant cartridge port (cartridge sold separately). Spray foam isocyanate reacts negatively with moisture, so this setup protects chemicals from humidity and prevents contamination. Includes Y-strainer, stainless fittings, check valve, flexible coupling, and camlock connectors.
• B-Side Assembly – SKU 236615
  Functions as the pressure relief and controlled air intake side. The check valve prevents backflow while allowing the drum to breathe under pump demand. Includes stainless fittings, Y-strainer, pipe nipples, aluminum camlocks, and PTFE sealing tape.

Key Benefits

• ✔️ Complete moisture-control and pressure-management system
• ✔️ A-side desiccant port protects isocyanate from humidity
• ✔️ B-side provides controlled air intake & pressure relief
• ✔️ Integrated check valves for backflow prevention
• ✔️ Fits drums with a 3/4” bung hole
• ✔️ Recirculates back to the pump, not the drum
• ✔️ Durable stainless, aluminum, and PVC components

Technical Features

• 1/2″ Y-strainer for debris protection
• Brass check valves for pressure relief and flow security
• Aluminum camlock fittings (Type D & Type F)
• 45° pipe swivel elbow for angled routing
• Camlock + pipe nipple + PTFE tape for a leak-proof seal
• Moisture-control desiccant port on the A-side

Applications

• Spray foam transfer pump systems
• Moisture-sensitive isocyanate handling
• Drum pressure relief and balanced ventilation
• Chemical recirculation to pump inlet

FAQs

Does this assembly work with all drums?
It fits chemical drums with a 3/4″ bung hole on the lid.

Does it recirculate to the drum or the pump?
This model recirculates back to the pump, not the drum.

Does the A-side include the desiccant cartridge?
No. The desiccant cartridge (SKU 157386) is sold separately.

Why does spray foam need moisture control?
Isocyanate reacts with moisture. A desiccant prevents curing, crystallization, and chemical contamination.

What does the B-side do?
It provides pressure relief and controlled air intake, preventing vacuum lock during pumping.