Liebherr refrigerators speak two code languages, depending on the line. Monolith built-ins such as the MRB BioFresh refrigerators show codes like BT011 or PH00010700 on their Touch & Swipe display. Liebherr’s CBS and HCB NoFrost refrigerator-freezers — refrigerator on top, two freezer drawers below — show F1 to F5 and a few alarm lights instead. The meanings below come from Liebherr’s own documents: the 2021 service manual for the Monolith MRB 2400, 3000 and 3600, and the CBS and HCB use and care manual. If your display shows something else, send us the model number and the code.
How a Monolith shows its codes
The code appears on the display when the fault occurs, and Liebherr’s service manual says pressing the display for two seconds shows the errors again. Write the code down, then open Setup and swipe to the device information screen, which lists the type, model, index, serial and service numbers from the type plate. That, plus the code, is what a technician needs.
Liebherr does not spell out the prefixes, but its table is consistent: BT codes are temperature sensors, GQ codes DC fans and PH codes communication errors between electronic modules. The table covers several models, so it includes freezer, IceMaker and wine-zone codes a refrigerator never shows, and next to each code it lists the emergency mode — how the appliance keeps running while that part is out.
Codes on a Monolith BioFresh refrigerator
These are the codes that match the components the MRB service manual lists:
| Code | Points at | What the refrigerator does meanwhile |
|---|---|---|
| BT011 | Refrigerator compartment air sensor | Compressor on 10 min, off 25 min |
| BT021 | Refrigerator compartment evaporator sensor | Compressor on 10 min, off 25 min |
| BT001 | BioFresh air sensor | Compressor on 10 min, off 25 min |
| BT061 | BioFresh-Plus air sensor | Compressor on 10 min, off 25 min |
| GQ021 | Refrigerator compartment fan | None listed |
| GQ033 | Condenser fan | None listed |
| PH00010000 | Control panel cannot reach the power unit | Keeps cooling, but cannot be operated |
| PH00010700 | Motor compartment module communication error | Compressor off, condenser fan runs nonstop |
| PH00010800 | Control panel cannot reach the refrigerator and BioFresh section | Compressor off |
| PH00012800 | SDB interface communication error | Works normally, cannot be networked |
One more sensor, BT071 (ambient air), shows only in the service menu; the fix Liebherr lists for it is the power board. Fan codes have a precise trigger: 30 seconds at half the prescribed speed or less — 600 rpm or less against a 1,200 rpm target, in Liebherr’s example. On the MRB one fan supplies cold air to the refrigerator and both BioFresh zones, so a weak fan affects all three; see refrigerator not cooling.
Freezer, IceMaker and wine-zone codes
BT031 and BT041, the freezer air and evaporator sensors, switch the compressor to continuous operation. BT032, EB035 and MA001 — the IceMaker sensor, heater and motor — switch the IceMaker off, and Liebherr notes they appear only once the IceMaker actually uses that part. GQ022 and GQ025 are the BioFresh and freezer fans. On wine units, BT012 to BT014 and BT022 to BT024 are zone sensors, GQ027, GQ029 and GQ031 are zone fans, and MA091 to MA093 mean a zone’s temperature limiting has kicked in, which stops the compressor for two hours. PH00010900 (freezer section) stops the compressor; PH00011000 (wine section) leaves it in its current state with no sensor control.
The codes that mean “call today”
PH00010700, PH00010800 and PH00010900 — the compressor is switched off and the appliance is not cooling. Keep the doors closed; Liebherr’s CBS and HCB manual gives the same advice to limit cold loss. And Liebherr lists the temperature alarm on the Monolith BioFresh refrigerator as “not featured,” so a warm fridge will not warn you by itself — the code is the warning.
Inverter flash codes. The variable-speed compressor’s inverter has its own diagnostic light, read by a technician in the base compartment. One flash every 15 seconds is normal; two, three or four flashes every 5 seconds mean no control signal from the power electronics, an inverter error or a compressor error. If the control signal is lost, the compressor falls back to a preset speed after 30 minutes.
Refrigerator sensor codes are less urgent: the refrigerator keeps cooling on a fixed timer rather than to your setting, so it can run warmer or colder than you want. Book a visit and keep a thermometer inside until then.
Monolith settings that look like faults
HolidayMode holds the interior at about 59°F on purpose, to save energy and prevent odors; check the main menu before assuming a failure. The door alarm is a red door symbol and three beeps after 180 seconds. And the compressor has an 8-minute switch-on delay and waits 20 minutes after each defrost, so a quiet spell is not a breakdown.
F1 to F5 and alarms on CBS and HCB models
On these models, F1 to F5 in the display means the appliance has a fault. The use and care manual does not say what each number means; it asks you to give the number to the technician with the type designation, service number and serial number from the model plate, inside on the left behind the BioFresh drawer. Keep the doors closed until the visit.
Flashing freezer temperature with the alarm light and a tone — the freezer is not cold enough: warm food just went in, warm air got in, or there is a fault. The alarm icon silences the tone; the display flashes until the temperature recovers, and if it never does, call. Power failure light — the freezer got too warm during an outage; touching Alarm shows the highest temperature reached, for about a minute. Two dashes — the freezer display only shows temperatures below 32°F, so dashes are normal for a few hours after start-up or an outage. A tone with a door open — the door alarm, after about 180 seconds.
Reminders, not faults: the water-drop symbol means the water filter is due; the air filter light means the toe-kick filter needs cleaning, which the manual covers. S is Sabbath mode: no door or temperature alarms and no lighting until it ends, automatically after 120 hours. A dead interior light is a service part — Liebherr says not to replace it yourself. The IceMaker needs the water supply open, the upper freezer drawer fully closed and the ice bin seated; a flashing light above its On/Off button means call service.
Why we don’t recommend guessing parts
A BT code points at a sensor, but the sensor, its connection and the board reading it all get checked before anything is ordered; a PH code says two modules stopped talking, not which one failed. Liebherr’s service menu also stores counters we read before quoting: operating hours, door openings, power failures and defrost cycles, including those that ran to the 50-minute limit. The Monolith MRB uses R600a, a flammable refrigerant, so sealed-system work belongs with a qualified technician; see sealed-system repair. We read the codes, test live, quote the actual repair, and the diagnostic fee is credited toward it.
Repair or replace?
Sensors, fans, modules and boards are worth repairing on a Liebherr. A compressor failure is the bigger conversation — check your warranty first: the plan printed in the CBS and HCB manual, for example, covers sealed-system parts through year 12 when the work is done by Liebherr’s authorized service.
Liebherr refrigerator repair across the Denver Metro
FiXiFY repairs Liebherr refrigerators and freezers across Denver, Aurora, Lakewood, Westminster and the metro — same-day in most areas, genuine OEM parts. See built-in refrigerator repair, refrigerator repair, or the Sub-Zero error codes guide.
BOOK ONLINECALL (303) 214-1240
FAQ
What does BT011 mean on a Liebherr refrigerator?
It points at the refrigerator compartment air sensor, the sensor that controls the fridge section and drives its temperature display. While the code is active, the control runs the compressor on a fixed cycle of 10 minutes on and 25 minutes off, so the fridge keeps cooling, but no longer to your setting.
What does PH00010700 mean on a Liebherr Monolith?
It is a communication error with the motor compartment module. In Liebherr’s emergency mode the compressor is switched off and the condenser fan runs nonstop, so the unit is not cooling. Keep the door closed and book service the same day.
What do F1 to F5 mean on a Liebherr fridge?
On Liebherr CBS and HCB NoFrost refrigerator-freezers, any F1 to F5 in the display means the appliance has a fault. The use and care manual does not publish what each number means, so write it down with the type, service and serial numbers from the model plate and give them to the technician.
Why is my Liebherr refrigerator beeping?
Most often it is the door alarm: both the Monolith and the CBS and HCB models sound after a door has been open about 180 seconds. On CBS and HCB models, a tone with a flashing freezer display and the alarm light means the freezer is not cold enough, and if it does not recover once the door is shut and nothing warm was added, it needs service.
FiXiFY Appliance Repair — 7030 E 46th Ave Dr, Unit A, Denver, CO 80216 · (303) 214-1240 · support@fixifycolorado.com