Chamberlain 8355 - Preparation; Safety Symbol and Signal Word Review; Check the Door; General Safety Warnings

2
Safety Symbol and Signal
Word Review
This garage door opener has been designed and
tested to offer safe service provided it isinstalled,
operated,maintained and tested in strict
accordance with the instructions and warnings
contained in this manual.
When you see these SafetySymbols and Signal
Words on the following pages,they will alertyou
to the possibility of serious injury or death if you
do not complywith the warnings that accompany
them. The hazard maycome from something
mechanical or from electric shock. Read the
warningscarefully.
Mechanical
Electrical
When you see thisSignal Word on the following
pages, itwill alertyou to the possibilityof damage
to your garage door and/or the garage door
opener ifyou do not complywith the cautionary
statementsthataccompanyit. Read them
carefully.
Check the Door
1. Disable locks and remove any ropes
connected to the garage door.
2. Liftthe door halfway up.Release the
door.If balanced, it should stay in
place, supported entirely by itssprings.
3. Raise and lower the door to check for
binding or sticking. Ifyour door binds,
sticks, or is out of balance,call a trained
door systems technician.
4. Check the seal on the bottom of the
door.Anygap between the floor and
the bottom of the door must not exceed
1/4 inch (6 mm).Otherwise, the safety
reversal system may notwork properly.
5. The opener should be installed above
the center of the door. Ifthere is a
torsion spring or center bearing plate
in the way of the header bracket, it may
be installed within 4 feet (1.2 m) to the
leftor rightof the door center.See
page 7.
Torsion Spring
Extension Spring
OR
To preventpossible SERIOUSINJURYor
DEATH:
• ALWAYS call a trained door systems
technician if garage door binds,sticks, or is
out of balance. An unbalanced garage
door mayNOT reverse when required.
• NEVER try to loosen, move or adjust
garage door, door springs,cables, pulleys,
brackets or their hardware, ALLofwhich
are under EXTREMEtension.
• Disable ALLlocks and remove ALLropes
connected to garage door BEFORE
installation and operating garage door
opener to avoid entanglement.
To preventdamage to garage door and
opener:
• ALWAYS disable locks BEFORE installing
and operating the opener.
• ONLY operate garage door opener at
120 V, 60 Hzto avoid malfunction and
damage.
Tools Needed
2
1
3/16
7/16
1/2
5/32
5/16
5/8
9/16
1/4
7/16
Preparation