LiftMaster 1355 1355 Manual - Page 5

Planning (Continued) ONE-PIECE DOOR INSTALLATIONS • Generally, a one-piece door does not require reinforcement. If your door is lightweight, refer to the information relating to sectional doors in Installation Step 11. • Depending on your door's construction, you may need additional mounting hardware for the door bracket (Step 11). WARNING Without a properly working safety reversal system, CAUTION persons (particularly small children) could be SERIOUSLY INJURED or KILLED by a closing garage door. • The gap between the bottom of the garage door and the floor MUST NOT exceed 1/4" (6 mm). Otherwise, the safety reversal system may not work properly. • The floor or the garage door MUST be repaired to eliminate the gap. ONE-PIECE DOOR WITHOUT TRACK Header Wall Slack in chain tension is normal when garage door is closed. FINISHED CEILING Support bracket & fastening hardware is required. See page 17. Motor Unit Wall-mounted Door Control Access Door Chain CLOSED POSITION Pulley Bracket Trolley Safety Reversing Sensor Safety Reversing Gap between floor Sensor and bottom of door must not exceed 1/4" (6 mm) Header Bracket Rail Door Bracket Header Wall Garage Door Straight Door Arm Curved Door Arm Emergency Release Rope & Handle ONE-PIECE DOOR WITH TRACK Access Door Safety Reversing Sensor Gap between floor and bottom of door must not exceed 1/4" (6 mm) Safety Reversing Sensor CLOSED POSITION Header Wall Chain Pulley Bracket Chain Trolley Header Curved Bracket Door Arm Rail Garage Door Door Bracket Straight Door Arm Emergency Release Rope & Handle 5