Autotrol 255 / 460

Summary

Product identification

• Product Line: Autotrol Control Valves
• Model: Autotrol 255 Control Valve - 460 Series

Technical Specifications

Valve Body & Components

• Valve Body Material: Glass-filled thermoplastic – NSF Listed material
• Rubber Components: Compounded for cold water – NSF Listed material
• Valve Materials Certification: WQA Gold Seal Certified to ORD 0902, NSF/ANSI 44, CE, ACS
• Weight (Valve with Control): 1.8 kg (4 lbs)

Operating Limits

• Recommended Operating Pressure: 1.38 - 8.27 bar (20 - 120 psi)
• Hydrostatic Test Pressure: 20.69 bar (300 psi)
• Water Temperature: 2-38°C (35-100°F)
• Ambient Temperature: 2-48.9°C (35-120°F) (Recommend use of outdoor cover for direct sunlight applications)

Controller Electrical

• Controller Operating Voltage: 12 VAC (Requires use of Pentair supplied transformer)
• Input Supply Frequency: 50 or 60 Hz (Controller configuration dependent)
• Motor Input Voltage: 12 VAC
• Controller System Power Consumption: 3 W average

Transformer Specifications

• Output Voltage: 12 VAC 150 mA
• Input Options: 230 VAC 50/60 Hz
• Plug Options: United Kingdom Plug, Mainland Europe Plug
• Requirement: All Controllers require the use of a Pentair supplied transformer.

Valve Connections

• Tank Thread: 2-½ inches – 8, male
• Brine Line: ¼ or ⅜ inch NPT, male; air check built into valve
• Inlet/Outlet Manifold: 1 inch NPT or BSPT, female; or ¾ inch NPT or BSPT, male; or ½ inch NPT or BSPT, male (thermoplastic)
• Distributor Tube (diameter): 27 mm (1.050 inch) or 20.6 mm (13⁄₁₆ inch)
• Drain Line: ½ inch (manifold dependent)
• Distributor Tube (length): 29 mm ± 3 mm (1-⅛ ± ⅛ inch) above top of tank

Performance

Flow Rate (Valve Only)

• Service @ 1.03 bar (15 psi) drop: 3.52 m³/h (15.5 gpm)
• Backwash @ 1.72 bar (25 psi) drop: 1.36 m³/h (6.0 gpm)
• Service Kv: 3.4 (Cv = 3.99)
• Backwash Kv: 1.0 (Cv = 1.20)

Brine Refill

• Fixed Rate: 0.33 gpm (1.25 Lpm)
• Optional Fixed Rate (small tanks): 0.14 gpm (0.53 Lpm)

Backwash Flow Control

• Sizing: Backwash flow controls sized for 5.0 gpm/ sq. ft.

Controller Features

460 Time Clock Characteristics

• Simple, precise electronic time clock (chronometric)
• 1- or 30-days regeneration setting
• 12 V operation

460i Volumetric Characteristics

• Same features as the 460 Time Clock, plus:
  • Capacity setting
  • Calendar override
  • 7 days variable reserve
  • 12 V operation
  • Standard manifold, 1 inch turbine

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror