Let’s face it, most of us don’t sit around thinking about how our fridge works. All we really care about is that our beer is icy cold when we swing that door open.
And really, what’s more important when you’re travelling this amazing country than rolling into that prized campsite, setting up with a cracking view, and pulling out that first cold one? That’s the moment you stand back and say – “We’re here! Living the Australian dream.”
But behind that golden moment is a bit of clever fridge magic.
It’s all about heat exchange! By cycling refrigerant through changes in pressure and state (from liquid to gas and vice versa), heat is removed from the cabinet and distributed into the atmosphere.
Caravan fridges come in two main styles:
3-Way Fridges (LPG / 12V / 240V) – Absorption System
3-way fridges work using heat, chemistry, and gravity.
- No compressor. Cooling is driven by a chemical reaction using ammonia, water, and hydrogen.
- A heat source (LPG flame, 12V, or 240V element) starts the process by boiling the ammonia solution.
- Cooling depends on chemistry, heat, and gravity to move the refrigerant around the sealed pipes.
- Because gravity plays a role, the fridge must be perfectly level to work properly.
- Cooling is steady, but efficiency drops in very hot and humid weather.
12V/240V Compressor Fridges – Mechanical System
- Use a compressor to pressurise and circulate the refrigerant.
- Much like your home fridge, but optimised for 12V use in caravans and RVs.
- Doesn’t rely on gravity, so it works even if the caravan is on a slope.
- Generally, it is more efficient in high ambient temperatures and cools down faster.
- Draws more electrical power, so battery capacity and solar setups are often required.
Caravan Fridge Comparison
Feature | 3-Way Fridge (Absorption – LPG / 12V / 240V) | Compressor Fridge (12V / 240V) |
Cooling Method | Chemical reaction using ammonia, water & hydrogen | Mechanical refrigeration using a compressor |
Power Source | LPG gas flame, 12V element, or 240V element | 12V battery (sometimes 240V via adapter) |
Key Principle | Heat + chemistry + gravity = cooling | Compression & expansion of refrigerant gas |
Level Requirement | Must be level to work properly | not gravity-dependent |
Efficiency in Hot Weather | Can struggle when temps climb | Tend to run longer and use more power at high ambient temps |
Startup & Cool-down | Slower to cool, steady once running | Slightly faster cool-down, temperature fluctuates as the compressor switches on and off |
Noise | Silent operation | Can be noisy when the compressor runs |
Power Usage | Very low gas usage on LPG, but high current draw on 12V and 240V | Moderate, steady draw on 12V (needs good battery/solar setup) |
Best For | Long stays off-grid with LPG, minimal power use | Frequent travel, caravans with large solar/battery setups |
Maintenance | Keep burner clean, flue clear, and stay level | Keep vents clean and clear of obstruction and ensure power supply is working properly |
What if my fridge isn’t getting cold? – Trouble shooting
3-way fridges
Issue | Symptom | Possible Cause |
Slow to Get Cold | Takes longer than 24 hours to cool down. Food and drinks stay warm inside. | Poor ventilation, hot weather, or a dirty burner. |
Chewing Through Gas | Your LPG bottle empties quicker than usual. | Burner or chimney needs cleaning, flame not burning efficiently. |
Doesn’t cool on 12V or 240V | Runs fine on gas but barely chills on 12V/240V | The 12V240V heating element may be faulty |
Freezer Cold, Fridge Warm | Ice in the freezer, but lukewarm food in the fridge. | Ventilation issues or a dirty burner. Heat isn’t being moved away efficiently. |
Flame Keeps Going Out | Burner works for a while, then goes out. Only stays lit while holding the Gas button. | Faulty flame sensor (thermocouple). This safety device tells the fridge if the flame’s burning — if it’s faulty, the gas shuts off. |
All Caravan Gas Man mobile technicians are fully licenced and qualified gas fitters, backed by Adam’s over 35 years of experience in the Gas and Caravan industry. With this strong foundation of expertise and hands-on knowledge, you can trust them to provide safe, reliable, and professional service—no confusing jargon, just down-to-earth, good service. Call Adam at Caravan Gas Man on 0402 116 427.
12V/240V fridges
Issue | Symptom | Possible Cause |
Fridge doesn’t cool properly | Items stay warm, or the fridge never reaches the set temperature. | Weak or insufficient 12V supply Damaged compressor or controller Faulty thermostat |
Excessive Battery Drain | Battery runs down quickly, or fridge shuts off when battery is low. | Insufficient Battery storage /Solar charging. Fridge temperature set too low so the compressor never cycles off. |
Fridge Turns On and Off Frequently (Short Cycling) | Compressor keeps starting and stopping. | Faulty thermostat. Overheating compressor due to poor ventilation. Voltage supply dropping under load. |
Freezer Cold, Fridge Warm | Ice in the freezer, but lukewarm food in the fridge. | Ventilation issues – faulty circulating fan. |
Fridge Won’t Start on 12V | Nothing happens when switched to 12V. | Blown fuse or tripped circuit breaker. Faulty power switch or control board. Voltage too low to start the compressor (<11V for many fridges). |
Overheating | Hot to touch, fridge cuts out. | Poor ventilation around fridge. Dirty or blocked heat exchanger or condenser fins. Running fridge on very high ambient temperatures without airflow. |
Leaks or Frost Build-up | Water inside fridge, or thick ice in freezer. | Blocked drain hole. Door seal not sealing properly. Ambient humidity is too high, combined with frequent door openings. |
Finally
Keep your caravan fridge in top shape! Regular cleaning and servicing ensures long life and icy-cold drinks every trip.
Quick Comparison Table
Feature | 12V/240V Fridge (Compressor) | 3-Way Fridge (Absorption) |
Cooling Speed | Fast on 240V | Slower but a steadier maintenance of temperature |
Power Options | 12V/240V only | 12V / 240V / Gas |
Off-Grid Efficiency | Needs a lot of battery storage | Most Efficient on gas |
Level Sensitivity | Can work on slopes | Must be level for gas |
Noise | Can be loud | Quiet (on gas) |
Size & Weight | Compact | Slightly bulkier |
Maintenance | Low | Low |
Safety (Gas Risk) | Safe | Requires LPG safety |