If your Subcold compressor fridge appears to switch on and off during operation, this is usually normal and does not indicate a fault.
Compressor fridges are designed to operate intermittently rather than run continuously. The compressor automatically starts and stops to regulate the temperature inside the appliance.
Why the Compressor Switches On and Off
The fridge uses an internal thermostat or temperature control system to monitor the temperature inside the appliance.
During normal operation, the fridge will automatically:
Switch the compressor on when the internal temperature rises above the required level
Continue cooling until the selected temperature is reached
Switch the compressor off once sufficient cooling has been achieved
Restart the compressor when the temperature begins to rise again
This repeated start-and-stop cycle is normal operation and allows the fridge to maintain a stable temperature without running the compressor continuously.
The compressor switching off does not mean that the fridge has lost power or developed a fault.
Why the Fridge May Cycle More or Less Frequently
The amount of time the compressor runs, and how often it switches on and off, can vary considerably.
The compressor may operate more frequently when:
The surrounding room temperature is high
The fridge has recently been switched on
The door is opened frequently
Warm food or drinks have recently been placed inside
The temperature setting is set colder
The fridge contains a large quantity of items
Ventilation around the appliance is restricted
The compressor may remain switched off for longer when:
The surrounding temperature is cooler
The selected internal temperature has already been reached
The door remains closed for extended periods
The fridge is lightly loaded
The appliance has been operating for several hours and the contents are already cold
These variations are expected and are part of normal temperature regulation.
Noises When the Compressor Starts or Stops
It is also normal to hear a noise when the compressor starts or switches off.
Depending on the model and installation, you may notice:
A brief click when the compressor starts
A click when the compressor switches off
A short humming or buzzing sound as the compressor begins operating
A slight vibration when the compressor starts or stops
A brief change in sound as pressure within the refrigeration system equalises
These sounds can be more noticeable in a quiet room and do not normally indicate a problem.
Bubbling, Gurgling or Gas-Like Sounds
You may also hear sounds from inside the refrigeration system while the fridge is running or shortly after the compressor switches off.
Normal refrigeration sounds can include:
Bubbling
Popping
Gurgling
Trickling
Flowing or liquid-like noises
These sounds are generally caused by refrigerant moving through the sealed cooling system.
The refrigerant changes pressure as it circulates through the appliance, which can produce noises that sound similar to flowing liquid or gas.
This is a normal characteristic of a compressor refrigeration system and does not normally mean that gas is leaking from the appliance.
Is the Start-and-Stop Cycle a Fault?
No. If the fridge is cooling correctly and the compressor periodically starts and stops, this is normally a sign that the temperature control system is working as intended.
A compressor fridge is not designed to run continuously at all times.
Once the required temperature has been reached, the compressor switches off to reduce unnecessary operation. It will automatically restart when further cooling is required.
Check the Fridge Is Operating Normally
To confirm that the appliance is operating correctly, check that:
The fridge reaches and maintains the expected internal temperature
The compressor restarts automatically when additional cooling is required
The appliance remains connected to a stable power supply
The door closes and seals correctly
Ventilation openings are not obstructed
There is adequate ventilation space around the appliance
There are no continuous grinding, scraping or unusually loud mechanical noises
If required, a separate fridge thermometer can be placed near the centre of the appliance to monitor the internal temperature over several hours.
Do not rely on a temperature reading taken immediately after opening the door, as warm room air entering the fridge can temporarily affect the reading.
When to Contact Subcold Customer Service
Please contact Subcold Customer Service if:
The fridge is no longer cooling correctly
The compressor does not restart even when the internal temperature rises
The appliance repeatedly loses all electrical power
The compressor attempts to start every few seconds but does not remain running
There is continuous or unusually loud clicking
You hear severe grinding, scraping or knocking noises
The appliance is becoming excessively hot
An error code or warning indicator is displayed
The internal temperature remains significantly warmer than the selected setting
When contacting us, please provide:
The fridge model
The serial or batch number
Your order number
The selected temperature or thermostat setting
The approximate room temperature
A description of how frequently the compressor switches on and off
Confirmation of whether the fridge is cooling correctly
A short video showing the appliance and any unusual noise, where possible
This information will help our Customer Service team determine whether the behaviour is normal compressor cycling or whether further troubleshooting is required.
In most cases, periodic compressor start-and-stop operation, brief noises when the compressor starts or stops, and bubbling, gurgling or refrigerant-flow sounds are all normal characteristics of a compressor fridge and are not a fault.