AP4 CLASSIC LTD.

Built For Controlled Extraction

 

In many landfill and remediation systems, excessive extraction creates more problems than it solves.

Uncontrolled flow can:

• Overwhelm storage systems
• Disrupt treatment processes
• Destabilize microbial balance
• Increase operational costs
• Cause silting and gas well disruption
• Reduce overall system efficiency

AP4 CLASSIC LTD. is engineered specifically to maintain stable, controlled extraction rates automatically — helping protect your system from over-pumping and unnecessary operational instability.

The result:
More predictable operation. Less adjustment. Greater system stability.

 

Why AP4 CLASSIC LTD.

 

Proven 

Built as part of the trusted AP4 CLASSIC Series — delivering reliable performance in harsh landfill and remediation environments.

Proactive

No throttling valves. No manual adjustments. No ongoing monitoring required.

Controlled

Fixed internal flow control maintains optimal extraction rates automatically — helping protect downstream systems and maintain operational balance.

 

Fixed Flow. No Adjustments.

 

AP4 CLASSIC LTD. is engineered to simplify controlled extraction by eliminating the need for:

• External throttling valves
• Constant flow adjustments
• Manual balancing
• Frequent operator intervention

Maximum Flow:

2.5 gpm (9.46 lpm)

 

Consistent flow performance helps:

• Protect sensitive treatment systems
• Reduce operational variability
• Simplify system management
• Improve long-term operational consistency

 

Built To Simplify System Control

 

Traditional flow control methods often require:

• Constant monitoring
• Valve adjustments
• Ongoing balancing
• Repeated operator intervention

AP4 CLASSIC LTD. simplifies operation by maintaining a stable, controlled extraction rate automatically.

That means:

• Less manual oversight
• Reduced operator workload
• Fewer adjustment errors
• More stable system performance

When control matters, LTD. keeps your system balanced.

 

What Makes AP4 CLASSIC LTD. Different

 

Built-In Flow Control

Integrated internal flow control automatically limits extraction rates without external throttling valves or manual balancing.

 

Protects Against Over-Pumping

AP4 CLASSIC LTD. helps maintain controlled flow automatically — reducing operational instability caused by excessive extraction.

 

Targeted Durability Upgrade

A welded lever pin enhances reliability compared to traditional press-fit designs.

 

Ideal Applications

 

AP4 CLASSIC LTD. is ideal for:

• Landfill gas well liquid management
• Controlled leachate extraction systems
• Sensitive treatment processes
• Systems requiring stable flow rates
• Operations where over-pumping creates disruption
• Sites seeking simplified flow management

Pump fittings sold separately.

 

Part of the AP4 CLASSIC Series

 

AP4 CLASSIC LTD. is part of a complete pump lineup built for harsh environments and simplified ownership.

Choosing the right pump

• Standard harsh conditions → AP4 CLASSIC Ultra
• High temperature → AP4 CLASSIC HI‑TEMP
• Extreme solids/fouling → AP4 CLASSIC XTREME
• Controlled flow → AP4 CLASSIC LTD

 

Specifications (Summary)

• Diameter: 3.6 in (9.1 cm)
• Maximum depth: 250 ft (76 m)
• Air pressure range: 5–120 psi
• Maximum flow: 2.5 gpm (9.46 lpm)

👉 Download the full technical data sheet for complete specifications and compatibility details.

 

FAQs

 

Does LTD. require throttling valves?

No. AP4 CLASSIC LTD uses fixed internal flow control, eliminating the need for external throttling valves and manual adjustments.

Why is controlled flow important?

Uncontrolled extraction can overwhelm storage systems, destabilize treatment processes, increase operational costs, and create unnecessary system disruption.

Is LTD. still designed for harsh environments?

Yes. LTD. is built on the proven AP4 CLASSIC platform and is engineered for harsh landfill and remediation environments.

 

Keep Your System Balanced

• Request a Quote
• Download the Data Sheet

Fixed flow. No adjustments. More predictable operation.

 

What Operational Stability Actually Feels Like

• Less manual balancing
• Fewer operator adjustments
• More stable treatment performance
• Reduced monitoring requirements
• Predictable extraction rates
• Confidence your system stays under control

 

• • Proprietary non-stick finishes on float and discharge tube to reduce solids buildup
• • 100% air-powered operation
• • Corrosion-resistant 316-grade stainless steel metallic parts
• • Reliable air control mechanism
• • Temperature ratings up to 180 °F, making it ideal for high temperature applications.
• • ATEX Certified
• • Functions under positive or negative (vacuum) pressure environments.
• • Does not require clean dry air to function properly and pumps particles up to 1/8 inch in diameter.
• • The AP4+ air valves can pass 90 weight oil without fouling.
• • Able to pump products with a specific gravity as low as .72
• • 5 Year Warranty

• • Increase landfill gas extraction rates.
• • Reduced risk of liquid leakage through liners and side slope failures.
• • Lower rates of odors and non-methane organic compounds.
• • Field tests have shown that the AutoPump® AP4 & AP4.5 Ultra will last up to 10 times longer between service events. Tested in the most severe applications.
• • Cleans in up to 50% less time than control group, determined by field tests
• • Simple disassembly with no fasteners and no cotter pins
• • AutoPumps require no surface timer-based controllers, bubblers or sensors in the well to operate.