Pentair FNS Plus FNSP 48 User Manual

Rev. G 6-27-03 1 P/N 190033
FNS
®
Plus Vertical Grid D.E. Filter Owner's Manual
SECTION I. FILTER INSTALLATION.
A. GENERAL INFORMATION.
1. The filter should be mounted on a level concrete slab. Position
the filter so that instructions, warnings and the pressure gauge
are visible to the operator. It also should be positioned so that
the piping connections, control valve and drain port are
convenient and accessible for servicing and winterizing.
2. Install electrical controls (e.g., on/off switches, timers, control
systems, etc.) at least five (5) feet from the filter. This will
allow you enough room to stand clear of the filter during
system start up.
3. Allow sufficient clearance around the filter to permit visual
verification that the clamp is properly installed around the tank
flanges, see Figure 1.
a. Tap the clamp with a mallet or similar tool to ensure uniform
loading during clamp tightening.
IMPORTANT SAFETY INSTRUCTIONS
READ AND FOLLOW ALL INSTRUCTIONS
SAVE THESE INSTRUCTIONS
Table of Contents
SECTION I. FILTER INSTALLATION. .......................................................................................... 1
SECTION II. FILTER OPERATION. ................................................................................................ 2
SECTION III. TROUBLE SHOOTING. ............................................................................................. 8
SECTION IV. TECHNICAL DATA. ............................................................................................. 9-10
WARRANTY ............................................................................................................... 11
Important Notice
Attention Installer.
This manual contains important information about the installation, operation and safe use of this product.
This information should be given to the owner/operator of this equipment.
WARNING
Before installing this product, read and follow all warning notices and instructions accompanying this filter. Failure to follow
safety warnings and instructions can result in severe injury, death, or property damage. Call (800) 831-7133 for additional free
copies of these instructions.
Figure 1.
Pentair Pool Products
1620 Hawkins Ave., Sanford, NC 27330 • (919) 774-4151
10951 West Los Angeles Ave., Moorpark, CA 93021 • (805) 523-2400

Pentair FNS Plus FNSP 48 Specifications

General

Model	FNS Plus FNSP 48
Filter Area	48 sq. ft.
Max Operating Pressure	50 PSI
Tank Material	Polypropylene
Number of Elements	8
Air Relief Valve	Yes
Drain Plug	Yes
Filter Type	Diatomaceous Earth
Inlet/Outlet Size	1.5 inch
Waste Line Size	1.5 inch

Summary

Filter Installation Guide

General Installation Information

General guidelines for filter placement, electrical controls, and clearance requirements.

Filter Operation Manual

General Operation Overview

Explains filter operation under pressure, max working pressure, and the role of the pressure gauge.

Operating Pressure and Diatomaceous Earth Use

Details on maximum working pressure, pressure gauge use, and diatomaceous earth requirement.

Clamp Installation Safety

Step-by-step guide for correctly installing the filter clamp to prevent lid blow-off.

System Restart Procedures

Procedures for safely restarting the filter system after servicing.

Precoating Filter Elements with DE

Instructions on preparing and applying diatomaceous earth for optimal filter performance.

Preparing Diatomite

Details on the type and quantity of diatomaceous earth needed for filter precoating.

Manual Filter Cleaning Steps

Steps for manually cleaning the filter, including disassembly and flushing.

Cleaning Filter with Separation Tank

Procedure for cleaning the filter using a separation tank system.

Filter Element Cleaning Guide

Instructions for disassembling and cleaning individual filter elements.

Internal Air Bleed Tube Cleaning

How to clean the internal air bleed tube for proper filter function.

Manual Air Relief Valve Cleaning

Step-by-step guide to cleaning the manual air relief valve.

Troubleshooting Common Filter Issues

Air Entry Dangers and Causes

Identifies dangers of air in the filter and common causes.

Pressure Gauge Reading Problems

Troubleshooting steps for a dropping pressure gauge reading.

High Pressure After Backwash

Actions to take if filter pressure remains high after backwashing.

Diatomite Entering Pool Fix

Steps to diagnose and fix diatomite entering the pool.

Technical Data and Parts List

FNS Plus Tank Assembly Components

Lists parts and their numbers for the FNS Plus Tank Assembly.

Filter Flow Rates and Pressure Loss

FNS Plus Filter Flow Performance

Provides flow rate data and pressure loss chart for FNS Plus filters.