Error light comes on when keying combination code

Open it with the key. Change the batteries and reset the code. You don't need to even use the key to open them, a rare earth magnet or a bump on the top will open them.

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Locksmiths agree If your safe doesn't have a key, skip Step 3.
Turn the dial to zero.
Insert your sentry safe key and turn it until the plunger pops out.
Turn the dial to the left (counterclockwise) three times to the first number of the combination (pass the first number of your combination two times, stopping on it the third time).
Turn the dial to the right (clockwise) two times to the second number of the combination (pass your second number once, stopping on it the second time).
Turn the dial to the left to the last number (stop the first time on your last number).
Pull the handle down; cracking the Fireproof Sentry Safe open.

I have a sentry safe csw 4747 Idont no tha combination
how do I do the safe a key and electronic key pad

You will need to contact customer service (either in the UK or US) for the replacement keys - without the keys you can't get into the safe. The key barrel is a secondary lock and needs to be unlocked before you can use the digital or dial combination.

Locksmiths advise these Opening instructions for sentry fireproof electronic security safes. Insert the tubular sentry key into the lock to the left of the key pad. Turn the key all the way to the right until the plunger pops out. Press the five-digit factory code. The green Proceed light will come on. Pull the handle down; to crack the sentry door open.

sentry safes opening instructions for 4 # combo locks
Turn the dial to zero.
Turn the dial to the left (counterclockwise) four times to the first number of the combination (pass the first number of your combination three times, stopping on it the third time).
Turn the dial to the right (clockwise) three times to the second number of the combination (pass your second number twice, stopping on it the third time).
Turn the dial to the left (counterclockwise) two times to the third number of the combination (pass the third number of your combination one time, stopping on it the second time).
Turn the dial to the right to the last number (stop the first time on your last number).
Pull the handle down to crack the sentry safe open.

Nice looking safe. You can download an owner's manual from sentrysafe.com.
Some safes have provisions for supplying power to the combo in event of battery failure.
I don't know how it is supposed to operate with key.

i am a locksmith that has worked on several of these. The safe is manufactuered with three types of lock mechanisms 1. combo dial 2. digital 3. advanced digital the advanced digital is what you have there are no green lights on it. look at the manual carefully there are 2 seperate sections on the digital key pads yours will be the second.

You have to press the program / enter button after you enter the code How to open electronic sentry safes.
Locksmith opening instructions manual for sentry fireproof electronic security safes. Insert the tubular sentry key into the lock to the left of the key pad. Turn the key all the way to the right until the plunger pops out. Press the five-digit factory code. The green Proceed light will come on. Pull the handle down; to crack the sentry door open

How to open electronic sentry safes.

Locksmith opening instructions manual for sentry fireproof electronic security safes. Insert the tubular sentry key into the lock to the left of the key pad. Turn the key all the way to the right until the plunger pops out. Press the five-digit factory code. The green Proceed light will come on. Pull the handle down; to crack the sentry door open

How to open electronic sentry safes.

Locksmith opening instructions manual for sentry fireproof electronic security safes. Insert the tubular sentry key into the lock to the left of the key pad. Turn the key all the way to the right until the plunger pops out. Press the five-digit factory code. The green Proceed light will come on. Pull the handle down; to crack the sentry door open.