LG Refrigerator Why does refrigerator make high pitches beep/whistling sound. It's intermittent and it isn't the same sound made when the doors are left open? If this is normal, is there a way to reduce the sound level? Thanks for your help.

LG LFX23961ST Support Manuals Warranty More LG

I just used the link above to get the Manuals on your LG. On page 31, they did the following CYA statements...

The defrost timer will click when the automatic defrost cycle begins and ends. The thermostat control (or refrigerator control, depending on the model) will also click when cycling on and off. Rattling noises may come from the flow of refrigerant, the water line, or items stored on top of the refrigerator .
Your refrigerator is designed to run more efficiently to keep your food items at the desired temperature. The high efficiency compressor may cause your new refrigerator to run longer than your old one, and
you may hear a pulsating or high-pitched sound.
You may hear the evaporator fan motor circulating the air through the refrigerator and freezer compartments.
As each cycle ends, you may hear a gurgling sound due to the refrigerant flowing in your refrigerator.
Contraction and expansion of the inside walls may cause a popping noise.
Water dripping on the defrost heater during a defrost cycle may cause a sizzling sound.
You may hear air being forced over the condenser by the condenser fan.
You may hear water running into the drain pan during the defrost cycle.

I bolded the statement. Sounds like you are going to have to get used to the sound.

Semper Fi,
Z

is this a loud whistling, like a dying bird stuck in your freezer, or is this a lower pitched, sort of gentle whistling sound. If its the former, you likely have a faulty freezer fan motor. replace
if its the latter, sounds like you may have a issue with the door damper, which allows the air flow from the freezer into the refrigerator. However, assuming you dont have any cooling problems, you didnt mention if you do, it may simply be a normal occurance, as some makes and models open and close this damper door automatically, and when it is closed, can sometimes cause a low whistling noise

Remove the drawers and locate the small round vent hole on the lower back wall. Place a piece of sturdy tape over the haole and re assemble unit...problem solved.

We have summarised all possible problem for this case here to this link
http://www.fixya.com/support/r6008187-side_side_refrigerator_whistling_sound

On the display panel press the right key that turns the door alarm on and off

We have summarised all possible problem for this case here to this link
http://www.fixya.com/support/r6008187-side_side_refrigerator_whistling_sound

This indicated obstruction of air flow. Is there a change in cooling temperatures also? Thanks, Sea Breeze

Freezer section evaporator fan motor bearing are going out. This would be indicted by a high pitched squealing noise. Have the fan motor replaced and it should solve your problem.

Yes, there is the compressor that has a tinny high pitch sound and the condenser fan motor running at the same time.  The compressor is a very highly efficient motor that doesn't require a lot of energy to run but it does run quite long and often to keep the temperatures cold.