Thermador Refrigerator Not Cooling: Causes and Fixes
Quick Answer
When a Thermador stops cooling, start by checking if the condenser coils are clogged with dust. Nine times out of ten, these high-end units just need a thorough cleaning or a reset of the electronic control board to restore proper temperatures.
Ignore a warm Thermador and you're looking at a dead compressor in a few weeks, and those run $800-1200 just for the part. I've shown up to plenty of these calls where a 20-minute coil cleaning would've saved the homeowner two grand. The good news is most of the time it's something simple, not the compressor itself.
Phillips #2 screwdriver, Vacuum with narrow brush attachment
Thermador Refrigerator Not Cooling: Causes and Fixes
Here's what I see constantly on Thermador service calls: the fridge is built into cabinetry so tight that air can't circulate, and nobody's cleaned the coils in three years. These are premium machines with premium compressors, but they still choke on pet hair and dust like any other unit. Most cooling failures on Thermadors run $150-400 to fix, unless you've let it go long enough that the compressor burned out.
Most Likely Causes
Based on aggregated repair data, here is the probability breakdown for this error code:
Dirty Condenser Coils45%
Evaporator Fan Failure25%
Defrost System Malfunction15%
Inverter or Compressor Issues10%
Control Board Glitch5%
Symptoms You May Notice
Milk and leftovers going bad 2-3 days faster than normal, even though the display still reads 37°F.
Ice cream in the freezer is soft or has that grainy refrozen texture, which means temps have been swinging for a while.
Compressor is running almost nonstop but the fridge never actually gets cold.
There's a solid sheet of ice covering the back wall of the freezer compartment, sometimes thick enough that you can't fully close the drawers.
Water pooling on the bottom shelf or leaking out the front, usually from the drain getting clogged with ice or debris.
Can you reset a Thermador refrigerator to clear the NOT-COOLING code?
Turn it off at the circuit breaker or pull the plug completely. Wait a full 10 minutes, not two, not five. Ten. This lets the capacitors drain and the control board fully reboot. When you restore power, listen for the compressor to kick on within a few minutes. Give the unit 4-6 hours to return to set temp before deciding the reset didn't work.
Tools Required for Diagnosis
Phillips #2 screwdriverVacuum with narrow brush attachmentMultimeterFlashlight or headlampThermometer (to verify compartment temps)Flathead screwdriver (for prying trim panels)
Diagnostic Checklist
Follow these steps in order. We start with the easiest external fixes before opening up the machine.
ComponentComponent Under Test
Expected Range20–50 ohms
ConditionIf Open (OL) or infinite, replace component.
Frequently Asked Questions
Why is my Thermador freezer cold but the fridge is warm?
That's almost always the evaporator fan or a frozen evaporator. The freezer coils make all the cold air for both sections, and the fan pushes that air into the fridge compartment through a duct. If the fan dies or ice blocks the duct, the freezer holds temperature okay because the coils are right there, but the fridge just stops getting cold air delivered. Sometimes it's also the damper that opens and closes the air duct between compartments. That little flap can get stuck shut. Check the fan first, it's easier to access and way more commonly the problem.
How often should I clean the coils on a Thermador?
Every six months minimum. If you have a dog or cat, do it every three months. I know nobody actually does this, including people who paid $8,000 for the thing, but it genuinely extends compressor life significantly. Set a phone reminder for April and October and just do it. Takes 15 minutes with a vacuum. The coils on most Thermador built-ins are either at the top behind a grille or at the bottom behind the kick plate. Pop it off, vacuum it out, done. That 15-minute job has probably saved me from replacing a compressor more times than I can count.
What does it mean if my Thermador is clicking?
Clicking when it tries to start usually means the compressor is struggling to kick on. Most common cause is a bad start relay, which is that small component on the side of the compressor. Pull it off and shake it. If it rattles, it's toast. Replacement is like $15-30 and takes five minutes. If that's fine, you might be looking at the inverter board or the compressor itself. Repeated clicking followed by silence, then clicking again is the classic symptom. Turn the unit off when you hear this because running a stalled compressor will kill it.
Can I reset my Thermador refrigerator to fix cooling?
Yeah, it's worth trying and it's free. The control board on these units can glitch, especially after a power fluctuation. Full power disconnect at the breaker for 10 minutes is the move, not just pressing the temperature controls. When you restore power, the board reinitializes and sometimes clears sensor errors that were causing the cooling to shut down. I've had this fix about 1 in 10 cooling calls completely, and on another 1 in 10 it temporarily fixes things, which tells me there's an underlying electrical issue. Reset first, then diagnose if it comes back.
Is it worth repairing a 12 year old Thermador?
Almost always yes. These units are designed to run 20+ years and a lot of them do. Parts are still available and reasonably priced. Even a new evaporator fan or control board at $300-500 for parts and labor is a fraction of what a new built-in costs. The only time I'd tell someone to walk away is if the compressor is shot AND the inverter board is failing AND the gaskets are cracked, basically everything going wrong simultaneously. A single issue? Fix it. These are genuinely well-built machines.
How long should a Thermador take to get cold after a reset?
Give it a solid 4-6 hours to get back to set temperature after a full power disconnect. The first hour or two it's just running to pull temps down, and if you keep opening the doors you'll slow that down. Put a thermometer in there and check at the 4-hour mark. Freezer should be at 0°F and fridge at 37°F. If you're nowhere close after 6 hours, the reset didn't fix the underlying problem and you need to run through the diagnostics above.
Models Known to Experience NOT-COOLING Errors
This repair applies to most Thermador refrigerators with this error code. Common model numbers include: