Refrigerators are noisy appliances. They make sounds that you might find odd or unexpected based on your previous model. The truth is, all refrigerator models have their own quirky set of noises ranging from creaks and moans to buzzing, hissing and even sizzling. Another common sound in a refrigerator is bubbling or gurgling sounds. Many refrigerator owners report hearing a bubbling or gurgling sound from their appliance and wonder what it is. There are a few different explanations and usually it is nothing to worry about.
Over the course of any refrigerator's cooling cycle the refrigerant gas is compressed, changed to liquid, boiled or vaporized, changed back into a gas and is pumped through a network of tubes designed to keep the unit cold through the process of thermodynamics. Throughout these changes and processes the refrigerant can often make some noise as it travels through the tubes located on the backside or inside of your refrigerator. A common sound of this refrigerant moving and changing states is gurgling or bubbling sounds. These noises are completely normal and a part of the refrigeration process.
You may sometimes hear a bubbling sound when you shut the door on your refrigerator or freezer compartment. Refrigerators are equipped with drains that allow the defrost system to get rid of the melted away frost on the evaporator coil quickly and neatly. The water drips into the drain and then travels down a tube to a pan beneath the unit. When you have the door open and then quickly shut the airtight door the air pressure from the door closing forces air into the drain and tube and potentially past the currently draining condensation. Imagine blowing into a straw submerged in a soda. It is a similar movement of air that can result in a similar gurgling or bubbling sound. There is no problem when this happens.
Water is fed to many refrigerators for a couple of purposes. Water travels through a line to fill the ice maker and water also travels through a line to supply the reservoir that connects to the water dispenser in some models. In addition to the hissing or whooshing sound you may hear as water flows to the appliance, you may also hear dripping or bubbling as the water sprays into the ice maker or chilled water dispenser reservoir.
Gas RV Refrigerators
If your refrigerator is a gas model such as those commonly found in recreational vehicles, then the gurgling or bubbling sound could be a repair issue. Bubbling noises could mean there is a cooling system leak and the hydrogen necessary for cooling these refrigerators is not available. The result is boiling water inside the unit. Yellow stains near the refrigerator may mean refrigerant has leaked out. Repairs for the leak and a recharge are in order.