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La Marzocco B.4.004

La Marzocco B.4.004 Wally Milk Check Valve Fitting for Drain Line

Regular price $61.44

This part ships directly from La Marzocco and stock is not guaranteed. Lead time averaging 7 to 9 business days for ground shipments, 1 to 2 business days for Overnight.

If unavailable, the item will be backordered. If you have any questions check parts sheets below description. Please email or chat to confirm availability prior to ordering.

Description Details

Prevent costly clogs and safeguard your espresso machine with the genuine Wally Milk Check Valve Fitting for Drain Line (Part \# B.4.004). This critical component is engineered specifically for the Wally Milk Steaming System's drain line, ensuring one-way flow. **If your Wally drain line keeps backing up,** or you are experiencing issues with milk residue causing blockages, this OEM check valve provides the definitive solution. Key features include high-durability, milk-resistant polymer construction and a precision-engineered internal mechanism designed for seamless integration and reliable operation within commercial coffee environments.

Installation of the B.4.004 check valve fitting is straightforward and essential for maintaining a sanitary and efficient drain system. The primary benefit is preventing back-siphonage—stopping milk and cleaning solution from flowing back into the steaming system or contaminating other lines—which is vital for machine hygiene and performance. Proper usage of this part guarantees that your Wally unit can rapidly and cleanly expel waste liquids, **solving the problem of slow or clogged milk steamer drains**. By ensuring proper drainage, you minimize maintenance downtime and extend the life of your entire automated steaming setup.

Designed to fit existing Wally Milk systems, this check valve maintains OEM performance specifications, guaranteeing maximum compatibility and longevity. Don't risk component failure or unsanitary conditions with aftermarket substitutes. Investing in the Wally Milk Check Valve Fitting for Drain Line is the proven way to restore optimal flow and sanitation to your professional espresso station. **Stop worrying about drain line odors or blockages**; replace your worn-out valve with the B.4.004 and maintain the high standards of consistency and cleanliness your café demands.

Descriptions are for reference only. We do our best to fill in the blanks when manufacturers don’t provide descriptions, but details can vary. We strongly recommend checking with the manufacturer for the exact part number you need. Ordering based on the part number—rather than the description—is the best way to ensure compatibility.

Frequently Asked Questions

This Part #B.4.004 fits La Marzocco machines, including the Wally Milk series. Compatibility may be specific to the machine's production year and model. Please consult the technical PDFs and compatibility data on this page to confirm a match for your specific unit before finalizing your purchase.

Our current database shows fitment for the Wally Milk series. However, many La Marzocco components are interchangeable across different platforms. If you have successfully installed Part #B.4.004 on a model we haven't listed, please let us know so we can update our records for the community.

If you are unsure of the fit, do not guess. To prevent downtime, please view our Compatible Parts Diagrams to check the exploded view PDF for your specific unit, or message our parts team for assistance.

Parts from La Marzocco including this wally milk check valve fitting for drain line ship directly from their warehouse. Please email or chat to confirm availability prior to ordering.
Yes. Part #B.4.004 is a 100% genuine OEM component sourced directly from the La Marzocco factory. Using original parts ensures your equipment maintains its factory-spec pressure ratings and safety certifications.
Lead times for La Marzocco parts typically range from 7 to 9 business days depending on availability. Next Day Air parts usually ship within 1 to 2 business days.
All La Marzocco parts come with a 365-day manufacturer's warranty. Contact us for specific warranty details.
All La Marzocco parts come with a 30 day return policy. Please see our refund policy or chat for more details.

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