Fleck 2850 AiQ NBP Filter Valve 1½" BSP – No DLFC

The Fleck 2850 AiQ NBP Filter Valve combines the proven Fleck 2850 heavy-duty brass valve platform with Pentair's latest Advanced-iQ (AiQ) controller and powerhead, providing modern electronic control for commercial and industrial automatic backwashing filtration systems.

Designed as the new-generation alternative to the Fleck 2850 Filter Valve previously supplied with the SXT controller, the AiQ platform provides an intuitive full-colour interface, simplified programming, USB-C connectivity and a modular powerhead designed to make installation, commissioning and servicing easier.

This is the NBP (No Bypass Piston) filter configuration. During a backwash or regeneration cycle, the NBP configuration prevents untreated water from passing through to service.

Please note: this valve is supplied without a DLFC (Drain Line Flow Control). The appropriate DLFC should be selected separately to suit the vessel size, filter media and required backwash flow rate.

Key Features

• Fleck 2850 heavy-duty brass control valve

• Advanced-iQ (AiQ) electronic controller and powerhead

• Designed for automatic backwashing filtration systems

• NBP – No Bypass Piston

• No untreated water to service during backwash

• Supplied without DLFC

• 1½" BSP inlet and outlet connections

• Continuous service flow up to 11.6 m³/h

• Maximum backwash flow up to 11.1 m³/h

• Working pressure: 1.8–8.5 bar

• Working temperature: 1–43°C

• 24 V, 50/60 Hz electrical supply

• 50 mm (DN40) distributor tube

• 1" NPT drain connection

• Suitable for filter vessels from 10" to 24" diameter

• Adjustable electronic cycles

• Up to 99 minutes available per cycle

• Full-colour multilingual display

• USB-C programming and data transfer

• Field-updateable controller

• Modular powerhead design for easier installation and servicing

• Multi-angle status light

Advanced AiQ Control

Pentair's Advanced-iQ controller provides a modern replacement for the traditional Fleck SXT control platform. Programming can be carried out directly through the controller, with a dedicated Filter Cycle available when configuring the valve.

The USB-C connection supports programming, data transfer, usage history retrieval, software updates, diagnostics and troubleshooting. The controller can also be programmed before installation, while flash programming allows predefined configurations to be transferred efficiently between multiple valves.

NBP – No Bypass Piston

The No Bypass Piston (NBP) configuration stops the supply of untreated water to service while the filter is carrying out its cleaning or backwash cycle.

This makes the NBP version particularly suitable for commercial and industrial applications where allowing untreated water downstream during backwash would be undesirable.

DLFC Selection

This version is supplied without a Drain Line Flow Control (DLFC).

The DLFC determines the backwash flow rate through the filter vessel and should be selected separately according to the filter media, vessel diameter and required media bed expansion.

Supplying the valve without a fixed DLFC allows it to be configured for a wide variety of filtration media and vessel sizes.

Typical Applications

The Fleck 2850 AiQ NBP Filter Valve is suitable for commercial and industrial automatic backwashing filters including activated carbon, multimedia, sediment and specialist filtration systems where the required backwash rate is determined by the media and vessel size.