Melted ice cream, spoiled food, WARM BEER!
Has this happened to you?
Odds are most (if not every) RV owner has experienced this problem including me.
Don’t fret there’s likely a simple solution to this perplexing problem.
Would you like to know what it is?
Lets get started.
When you confront a problem, you begin to solve it.
– Rudy Giuliani
Why your refrigerator isn’t cold inside
If your refrigerator is original chances are it’s an absorption refrigerator. If not original theres a good chance the replacement is another absorption refrigerator.
The basic design of the absorption refrigerator is that it heats a liquid that turns into a gas. The gas slithers thru tubing and along the way absorbs heat (from inside the refrigerator).
The heat is then released (outside the refrigerator). Extracting the heat reduces the internal temperature.
Simply stated, the refrigerator needs heat to pull out the cold.
The problem is your refrigerators heater isn’t making enough heat (or any heat at all).
Curious how this actually works?
Theres an excellent diagram and detailed explanation of the process here.
The problem is there’s not enough heat
Theres a good chance this “Big” problem will requires a simple fix.
Let’s start with the basics.
Bear with me as we walk thru steps that may seem like a waste of time (they are not).
Reason #1: No voltage
The refrigerator needs electrical power to work. The electronics need DC voltage to activate the heating/cooling process. DC voltages flows from the RV batteries.
Troubleshoot steps:
- Verify DC voltage is getting to the refrigerator. Open the refrigerator door and verify the interior light comes on? If the light does not come on verify the bulb is good. If still no light check for voltage at the light socket (inside fridge). Expect 12 volts DC. If still no voltage start checking voltage at the batteries. Trace the wire(s) to the refrigerator (most often found on the backside of the fridge).
- Next, locate the temperature controls. Verify the “On/AC/Elec” indicators ar on. Refrigerators with temperature dials may not have any indicator lights. If your refrigerator is not getting at least 12 volts DC it will not work. Check for blown fuses.
- Third, verify the outlet the refrigerator plugs into has 120 volts AC. Unplug the refrigerator from the outlet and plug in a hair dryer or similar item to the outlet. If the hair dryer does not work check for tripped circuit breakers. This may be obvious but, verify the hair dryer works before trusting it.
The absorption refrigerator control board needs DC voltage to operate. The refrigerator will not work without it. Low voltage, anything below 12 volts can cause funky results.
Reason #2: No heat
The process starts by heating the liquid inside the tubing. The tubing located on the backside of the refrigerator.
Troubleshooting steps:
- Set the refrigerators temperature control to max cold.
- Set the refrigerator source mode to “AC” at the control panel. Give the electric element 30 minutes to heat up. Then using a laser thermometer check the temperature at the base of the flue. The temperature needs to be high enough to boil the ammonia mixture inside the cooling tubes.
- Repeat on “Gas” mode. First verify the gas is flowing. If the cooktop is gas a quick check is to light a burner. In gas mode a blue flame may be visible at the base of the flue. If no flame is present verify the flame igniter is working. You should hear the click, click, click when the system is attempting to start the flame.
Without good strong heat the refrigerator will not get cold.
Reason #3: No cooling
After boiling the liquid cooling must occur. Gravity draws the cooled mixture down the tubes.
Troubleshooting steps:
- Shine a light up the back side of the refrigerator. Verify the cooling fins are clear and clean. Also verify the vent to the outside at the top is clean and clear. This vent allows the heat to escape out of the compartment. Clean the fins and vents so cool air will flow in at the base of the refrigerator and out the top of the cavity.
A common problem is the refrigerator gets cool but not cold. Improving the airflow behind the refrigerator may help. Try placing a small fan behind the refrigerator to move the air.
Reason #4: Restricted flow
The liquid needs to flow thru the tubing aided by gravity. These tubes form a “Z” pattern with only a slight drop.
Troubleshooting steps:
- Verify there is no visible damage to the cooling tubes (backside of refrigerator).
- The RV needs to be level (close to it) for gravity to work. A small bubble level placed inside the refrigerator will verify. Check for level front to back and side to side.
If possible slide a vacuum hose with a soft brush attachment behind the refrigerator. Suck the dirt, dust and cobwebs out. Make sure the refrigerator is off or you may get burnt.
Reason #5: Low coolant
I’m referring to the liquid inside the cooling tubes.
Troubleshooting steps:
- Open the freezer door and suck in through your nose. Repeat for refrigerator compartment. If it smells like amonia the coolant is leaking out. The cooling unit needs repair or replacement. The chemicals inside the tubing can be dangerous and requires a sealed system. Replacing the cooling unit is a job best left to a professional. Replacing the entire refrigerator is within most DIY owners capability.
The goal here is to identify and rule out the common areas of trouble.
With some skilled diagnostic work and luck.
You’ve identified the reason your refrigerator is not cold.
And, if you’re lucky the temperature dial got bumped, a circuit breaker tripped or you found a blown fuse.
Fixing your refrigerator begins with simple diagnostics that every RV owner can do
The goal with this article is to identify the reason your refrigerator is not cold.
Identifying the reason may not solve the problem.
But you’ve eliminated the non-problem areas.
RV technicians (good ones) charge hefty fees to complete these simple tasks.
Tasks you can complete with a volt meter, flashlight, thermometer and a hair dryer.
Imagine the looks when you tell friends you fixed the refrigerator with a hair dryer!
