RV fridge not cooling: absorption and 12V compressor fridge troubleshooting

Two kinds of RV fridges

• Absorption fridges (often two-way propane/120V, or three-way with 12V) use heat to drive a refrigerant solution through sealed tubes on the back of the fridge. No compressor. They're silent, but slow to cool and sensitive to ventilation and level.
• 12V compressor fridges work like a household fridge running on DC power. They cool quickly but depend on healthy battery voltage.

Look at the fridge's label or manual to see which one you have.

Danger: If you smell ammonia, see yellow powder or residue on the back of an absorption fridge, or notice a strong chemical smell, turn the fridge off and unplug it, ventilate the RV and have it inspected. These are signs of a leaking cooling unit. The solution is under pressure and can contain chemicals that are harmful. Never try to repair a cooling unit yourself. Propane fridges have burners and flues, so follow the propane safety advice in RV propane problems: smells, weak flames, regulator issues and leak testing.

First: give it time and set expectations

Absorption fridges can take many hours to reach temperature from warm, often 8 to 24 hours depending on the model and conditions. Before a trip, turn it on well in advance and load it with already-cold food. Putting a lot of warm items in at once can overwhelm it. A fridge thermometer beats guessing: aim for around 3 °C in the fridge section and -15 °C or colder in the freezer as general food-safety targets.

Absorption fridge: check level and ventilation

1. Level: Absorption fridges need the RV to be reasonably level when parked. Modern units are more tolerant than old ones, but a badly off-level fridge can stop cooling and, if run that way for a long time, damage the cooling unit. Check your manual's tolerance.
2. Ventilation: The cooling unit sheds heat through the outside wall vent (and usually a roof vent). Check that vents aren't blocked by nests, leaves, a parked vehicle or snow. On hot days, a 12V fridge vent fan behind the fridge helps. Many newer fridges have one built in.
3. Inside airflow: Don't pack it so tight that air can't circulate around the fins. A small battery fridge fan evens out temperatures.
4. Door seal: Close the door on a piece of paper. If it slides out easily, the gasket isn't sealing there. Clean the gasket and check the hinges.

Absorption fridge: works on gas but not electric

• Check the fridge's 120V supply. It often plugs into an outlet behind the outside access panel. That outlet may be on a tripped GFCI or breaker. See RV outlets not working on shore power: GFCI, breakers and pedestal checks.
• Check the fuses on the fridge's control board (behind the outside access panel). Use a Digital multimeter (auto-ranging, with DC amps) to check them with power off.
• The heating element may have failed. With power off and wires disconnected, an element showing an open circuit (infinite resistance) has burned out. Elements are replaceable on most models but are often tucked into insulation behind the fridge.

Absorption fridge: works on electric but not gas

• Check that propane is on and other appliances light. Purge air from the lines by lighting the stove.
• Listen for ignition clicking. Watch for a flame through the outside access panel, if you can see the burner.
• Burner and flue: Rust flakes, soot or spider webs in the burner or flue reduce heat. Cleaning the burner, orifice and flue is routine maintenance, but the orifice is delicate and must not be enlarged or damaged. If you're not confident, have a technician do it.
• Check 12V power to the control board. Most absorption fridges need 12V to run their controls in any mode.

Absorption fridge: doesn't cool in any mode

If the fridge has power, heat is being applied (the boiler area at the back gets hot; an infrared thermometer helps) and the vents are clear, but the cooling fins inside stay warm, the cooling unit may have failed. Signs include an ammonia smell, yellow residue, or a boiler that's very hot with no cooling at all. Cooling units can be replaced, but often the cost makes a new fridge or a conversion to a 12V compressor fridge worth comparing. Get a professional assessment.

12V compressor fridge troubleshooting

• Battery voltage: Compressor fridges have low-voltage cut-outs to protect your battery. A low or sagging battery (or thin wiring causing voltage drop) can make the fridge stop. Measure voltage at the fridge while the compressor runs. See RV battery not charging: how to troubleshoot the converter and 12V system.
• Fuse and connections: Check the fridge's DC fuse and terminal connections.
• Ventilation: Compressor fridges need airflow around the condenser too.
• Error codes: Many show codes on a display or blink an LED.

Cold-weather notes for Alberta

Absorption fridges can behave oddly in cold weather. Some manufacturers offer winter vent covers for outside vents in cold conditions to keep the cooling unit operating properly. Check your fridge maker's guidance. In storage, prop the doors open and clean the fridge to prevent mould and odours.

Maintenance checklist

• Clean the burner area and flue annually (gas models), or have it done.
• Check vents and the area behind the fridge for nests and debris each spring.
• Inspect the cooling unit area for residue or odour.
• Check door gaskets.
• Some manufacturers have issued recalls on certain fridge models. Check the manufacturer's site and Transport Canada's recall database using your model and serial number.

When to call a pro

Any cooling unit leak or ammonia smell, gas burner or orifice service you're unsure of, control board replacement, or a fridge that won't cool after you've confirmed power, heat and ventilation.