Chamberlain Security + 3850PC - User Manual

The Chamberlain Group, Inc.
845 Larch Avenue
Elmhurst, Illinois 60126-1196
www.liftmaster.com
GARAGE DOOR OPENER
Model 3850PC
For Residential Use Only
Owner’s Manual
■ Please read this manual and the enclosed safety materials carefully!
■ Fasten the manual near the garage door after installation.
■ The door WILL NOT CLOSE unless the Protector System
®
is connected and properly
aligned.
■ Periodic checks of the opener are required to ensure safe operation.
■ The model number label is located under the light lens on the left side panel of your
opener.
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Chamberlain Security + 3850PC Specifications

General

Motor Type	DC
Safety Sensors	Yes
Battery Backup	Yes
Max Door Height	7 feet
Smart Technology	Yes
Warranty	Lifetime

Summary

Preparing Your Garage Door

Tools Needed

Garage Door Opener Assembly

Attach the Rail to the Motor Unit

Connects the opener rail to the motor unit using provided bolts.

Set the Belt Tension

Adjusts the belt tension for optimal opener operation.

Attach the Belt Cap Retainer

Installation Step 1: Determine Header Bracket Location

Installation Step 2: Install the Header Bracket

Installation Step 3: Attach the Rail to the Header Bracket

Installation Step 4: Position the Opener

Installation Step 5: Hang the Opener

Installation Step 6: Install the Door Control

Installation Step 9: Attach the Emergency Release Rope and Handle

Installation Step 10: Electrical Requirements

Installation Step 11: Install The Protector System

Installing the Safety Sensor Brackets

Mounting and Wiring Safety Reversing Sensors

Aligning the Safety Reversing Sensors

Explains how to align the sensor eyes for proper operation.

Installation Step 12: Fasten the Door Bracket

One-Piece Door Bracket Installation

Installation Step 13: Connect Door Arm to Trolley

One-Piece Door Arm Assembly

Adjustment Step 1: Program the Travel Limits

Adjustment Step 2: Set the Force

Adjustment Step 3: Test the Safety Reversal System

Adjustment Step 4: Test The Protector System

Operation

Important Safety Instructions

Crucial safety guidelines for operating the garage door opener.

Using the Wall-Mounted Door Control

Using the Remote Control

Troubleshooting Problems

Diagnostic Chart

Programming

Add or Reprogram a Hand-held Remote Control

Erase All Codes From Motor Unit Memory

Add, Reprogram, or Change Keyless Entry PIN