Bosch Heat Pump Error Codes — Meanings, Causes & Repair in Greater Vancouver

Seeing a fault code on your Bosch heat pump? This guide explains what the most common Bosch heat pump error codes mean, what’s safe to check yourself, and when to call HeatLand’s licensed HVAC technicians for Bosch heat pump repair across Metro Vancouver and the Fraser Valley.

The codes below apply across common Bosch models (Climate 5000, IDS, BOVA). Meanings follow Bosch’s documented fault codes — always confirm against your unit’s own manual, because exact wording can vary by model, control board and firmware.

How to read Bosch heat pump error codes

Bosch HVAC uses two different fault-code families depending on the product line. (1) CLIMATE 5000 DUCTLESS mini-splits show a two-character alphanumeric code on the indoor-unit display or as a blinking-LED pattern: E0-EC and Ex codes for indoor-unit / communication faults, F0-F6 for outdoor sensors and fan, and P0-P5 for protection (voltage, IPM, compressor). Bosch states the codes are four digits shown two at a time on the LED, and that the most common are E1, P0 and P3. (2) The IDS and BOVA central inverter heat pumps share one outdoor-unit code table shown on the outdoor control-board LED: C3 / E4-E9 (sensors, voltage, fan, EEPROM), H0/H5/H8 and F1 (control / IPM / transducer), P0-P8 and PH (protection). On IDS/BOVA the board also shows non-fault 'system protection status' letters (L, D, P, F, C, U, A, dF) followed by the compressor frequency in Hz – these mean the unit is intentionally running in a limited/derated condition, not that it has failed. An asterisk-marked fault (e.g. H5) latches a lockout that needs a hard restart by a technician.

Bosch heat pump error codes & what they mean

These are the Bosch heat pump codes our Greater Vancouver technicians see most. Anything marked pro repair involves electrical, refrigerant, sensor or control-board work that must be done by a licensed HVAC technician — never open the indoor/outdoor unit or refrigerant lines yourself.

Code	What it usually means	Common causes	Safe to check yourself
E0	Climate 5000 ductless: indoor unit EEPROM error (the indoor control board's memory chip could not be read/written correctly) pro repair	Indoor control board (PCB) fault or corrupted EEPROM; Power surge or brown-out during operation; Loose connector on the indoor PCB	Turn the system off at the breaker for a few minutes, then restore power once to allow a fresh start-up
E1	Climate 5000 ductless: communication error between the indoor unit and the outdoor unit (no valid data is being exchanged over the interconnecting cable). One of Bosch's most common Climate 5000 codes pro repair	Outdoor unit lost power or its breaker/disconnect tripped; Loose, corroded, reversed or damaged communication wiring between indoor and outdoor units; Failed indoor or outdoor control PCB	Confirm both the indoor and outdoor units have power and that no household breaker is tripped; Check that the disconnect switch near the outdoor unit is on; Turn the system off at the breaker for a few minutes, then restore power once
E3	Climate 5000 ductless: indoor fan speed error – the indoor fan is not turning at the commanded speed (or its feedback signal is lost) pro repair	Indoor blower wheel jammed or obstructed; Failed indoor fan motor; Loose indoor fan motor connector	Turn the system off at the breaker for a few minutes, then restore power once; Make sure the indoor air filter is clean and the supply/return airflow is not blocked by furniture, curtains or debris
E4	Climate 5000 ductless: indoor return-air temperature sensor error (the room-air thermistor is open or short circuited) pro repair	Failed room-air thermistor; Loose or damaged sensor harness/connector on the indoor PCB; Indoor control board fault	Turn the system off at the breaker for a few minutes, then restore power once; Confirm the indoor unit's air intake is not blocked
E5	Climate 5000 ductless: indoor coil temperature sensor error (the evaporator-coil thermistor is open or short circuited) pro repair	Failed indoor coil thermistor; Loose or pinched coil-sensor wiring; Indoor control board connector fault	Turn the system off at the breaker for a few minutes, then restore power once; Make sure the indoor air filter is clean so the coil is not iced over
EC	Climate 5000 ductless: low refrigerant detected (the system has sensed a refrigerant shortage / possible leak) pro repair	Refrigerant leak in the lineset, coil, or flare connections; Undercharge from improper installation; Faulty sensor logic on a low-charge system	Confirm the outdoor unit is clear of snow, leaves and debris and that airflow is unobstructed; Make sure the indoor filter is clean
F0	Climate 5000 ductless: outdoor current overload sensed (the outdoor unit detected excessive current) pro repair	Compressor or inverter overload; Restricted outdoor airflow / dirty outdoor coil; Low line voltage	Clear any snow, leaves or debris from around the outdoor unit so air can flow freely; Turn the system off at the breaker for a few minutes, then restore power once
F1	Climate 5000 ductless: outdoor ambient temperature sensor error (the outdoor air thermistor is open or short circuited). NOTE: on IDS/BOVA central units, F1 means something different – IPM module protection pro repair	Failed outdoor ambient thermistor; Loose or corroded sensor connector on the outdoor PCB; Outdoor control board fault	Turn the system off at the breaker for a few minutes, then restore power once; Confirm the outdoor unit is not obstructed
F2	Climate 5000 ductless: outdoor coil temperature sensor error (the condenser-coil thermistor is open or short circuited) pro repair	Failed outdoor coil thermistor; Damaged or loose sensor harness on the outdoor coil; Outdoor control board connector fault	Turn the system off at the breaker for a few minutes, then restore power once; Clear debris from around the outdoor coil
F3	Climate 5000 ductless: compressor discharge temperature sensor error (the discharge-line thermistor is open or short circuited) pro repair	Failed discharge-temperature thermistor; Loose or damaged sensor lead at the compressor; Outdoor control board fault	Turn the system off at the breaker for a few minutes, then restore power once
F4	Climate 5000 ductless: outdoor unit EEPROM error (the outdoor control board's memory chip could not be read/written correctly) pro repair	Outdoor control board (PCB) fault or corrupted EEPROM; Power surge during operation	Turn the system off at the breaker for a few minutes, then restore power once
F5	Climate 5000 ductless: outdoor unit fan speed error – the outdoor fan is not turning at the commanded speed (or its feedback is lost) pro repair	Outdoor fan blade obstructed by ice, leaves or debris; Failed outdoor DC fan motor; Loose fan-motor connector	Clear snow, ice, leaves and debris from around and on top of the outdoor unit; Turn the system off at the breaker for a few minutes, then restore power once
F6	Climate 5000 ductless: indoor coil outlet temperature sensor error (the evaporator-outlet thermistor is open or short circuited) pro repair	Failed coil-outlet thermistor; Loose or pinched sensor wiring; Indoor control board connector fault	Turn the system off at the breaker for a few minutes, then restore power once; Make sure the indoor air filter is clean
P0	Climate 5000 ductless: inverter module (IPM) error – the outdoor inverter power module has reported a fault. One of Bosch's most common Climate 5000 codes. NOTE: on IDS/BOVA central units, P0 means control-board (TF) over-temperature protection pro repair	Inverter / IPM power module overheating or failure; Restricted outdoor airflow causing high module temperature; Compressor fault drawing excessive current	Clear any obstruction around the outdoor unit so it can cool properly; Turn the system off at the breaker for several minutes, then restore power once
P1	Climate 5000 ductless: high or low voltage protection – the supply voltage to the unit is outside the allowed range. NOTE: on IDS/BOVA central units, P1 means high-pressure switch (HPS) protection pro repair	Utility supply voltage too high or too low (brown-out); Loose or undersized power wiring; Failed inverter/control board voltage sensing	Check whether other appliances on the same circuit are also affected by low/high voltage; Turn the system off at the breaker for a few minutes, then restore power once
P3	Climate 5000 ductless: outdoor unit low-temperature lockout (the outdoor ambient is below the operating limit, so the compressor is locked out). One of Bosch's most common Climate 5000 codes. NOTE: on IDS/BOVA central units, P3 means compressor over-current protection pro repair	Outdoor temperature below the unit's minimum operating range; Outdoor ambient sensor reading low; Sensor or control board fault if it appears in mild weather	In very cold weather, this can be normal protective behavior – allow the unit to resume on its own as temperatures rise; Confirm the outdoor unit is clear of snow and ice
P4	Climate 5000 ductless: compressor drive error (the inverter could not drive the compressor correctly) pro repair	Compressor electrical fault (open/shorted winding); Inverter / IPM board fault; Loose compressor wiring	Turn the system off at the breaker for several minutes, then restore power once
P5	Climate 5000 ductless: mode conflict (an indoor unit is calling for a mode that conflicts with another – e.g. one zone calling for heat while another calls for cooling on a multi-zone system). NOTE: on IDS/BOVA central units, P5 means condenser-coil (T3) temperature protection in cooling pro repair	Two indoor heads set to conflicting modes (heat vs cool) on a multi-zone outdoor unit; Thermostat/remote mode settings not matched across zones	On a multi-zone system, set all indoor units to compatible modes (all heating or all cooling) using each remote; Turn the system off at the breaker for a few minutes, then restore power once
C3	IDS / BOVA central inverter: the coil sensor (T3) is mis-seated / faulted in cooling mode pro repair	Outdoor coil temperature sensor (T3) loose or out of its mounting pocket; Failed T3 thermistor; Loose sensor connector on the outdoor control board	Turn the system off at the breaker for a few minutes, then restore power once; Confirm the outdoor unit is clear of debris
E4	IDS / BOVA central inverter: temperature sensor fault among T3, T4, T3L, T5 or TF (one of the outdoor thermistors is open, shorted or reading out of range) pro repair	Failed outdoor thermistor (coil, ambient, liquid line, discharge or module sensor); Sensor in the wrong location or poorly seated; Loose or corroded sensor connector on the control board	Turn the system off at the breaker for a few minutes, then restore power once; Make sure the outdoor unit is not blocked by snow, leaves or debris
E5	IDS / BOVA central inverter: high/low voltage protection – the supply voltage is outside the allowed window (roughly above ~270 V or below ~172 V on the inverter's sensing) pro repair	Utility supply voltage too high or too low; Loose, corroded or undersized power wiring; Failed control/inverter board voltage sensing	Check whether other appliances are also affected by abnormal voltage; Turn the system off at the breaker for a few minutes, then restore power once
E6	IDS / BOVA central inverter: DC fan motor fault (the outdoor variable-speed fan motor is not running correctly or is not reporting feedback) pro repair	Outdoor fan blade jammed by ice, leaves or debris; Failed outdoor DC fan motor; Loose or damaged fan-motor wiring/connector	Clear snow, ice, leaves and debris from around and on top of the outdoor unit; Turn the system off at the breaker for a few minutes, then restore power once
E7	IDS / BOVA central inverter: compressor discharge sensor (T5) is mis-seated / faulted pro repair	Discharge-temperature sensor (T5) loose or out of its pocket on the compressor discharge line; Failed T5 thermistor; Loose sensor connector on the control board	Turn the system off at the breaker for a few minutes, then restore power once
E9	IDS / BOVA central inverter: EEPROM fault (the outdoor control board's memory chip could not be read/written correctly) pro repair	Outdoor control board (PCB) fault or corrupted EEPROM; Poor connector contact / improper board installation; Power surge during operation	Turn the system off at the breaker for a few minutes, then restore power once
H0	IDS / BOVA central inverter: communication fault in the main control chip (an internal communication error on the outdoor control board) pro repair	Outdoor main control board fault; Loose internal board connector; Electrical noise or power-supply disturbance	Turn the system off at the breaker for a few minutes, then restore power once
H5	IDS / BOVA central inverter: low-pressure (P2) protection has tripped 5 times within 100 minutes, so the system has latched into lockout. This is a hard fault that requires a manual (hard) restart by a technician after the cause is corrected pro repair	Repeated low-pressure trips from low refrigerant charge or a leak; Restricted airflow over the coils; Blocked filter-drier / metering device	Confirm both the indoor and outdoor coils have unrestricted airflow (clean filter, clear outdoor unit); Do not attempt to clear the lockout yourself – this latched fault needs a licensed technician
H8	IDS / BOVA central inverter: pressure transducer (PT) fault – the system pressure sensor is reading incorrectly or has failed pro repair	Failed pressure transducer; Loose or damaged transducer wiring/connector; Outdoor control board fault	Turn the system off at the breaker for a few minutes, then restore power once
P0	IDS / BOVA central inverter: control-board (module) temperature protection (TF) – the inverter power module has overheated. NOTE: on Climate 5000 ductless units, P0 means IPM module error pro repair	Restricted outdoor airflow / dirty outdoor coil causing high module temperature; Failed outdoor fan motor; Inverter / module cooling fault	Clear any obstruction around the outdoor unit so it can cool properly; Turn the system off at the breaker for several minutes, then restore power once
P1	IDS / BOVA central inverter: high-pressure switch (HPS) protection – the mechanical high-pressure switch has opened (it opens at about 580 PSIG). NOTE: on Climate 5000 ductless units, P1 means high/low voltage protection pro repair	Dirty or blocked coil (outdoor in cooling, indoor in heating); Failed or obstructed fan (outdoor in cooling, indoor in heating); Overcharge of refrigerant	Make sure the air filter is clean and indoor airflow is not blocked; Clear leaves, snow and debris from the outdoor coil; Turn the system off at the breaker for a few minutes, then restore power once
P2	IDS / BOVA central inverter: low-pressure protection in cooling or heating, sensed by the pressure transducer (PT). (In cooling, the low-pressure protection trips at about 43.5 PSI sustained for 5 minutes.) pro repair	Low refrigerant charge / refrigerant leak; Restricted airflow over the evaporator coil (dirty filter, blocked return); Blocked metering device or filter-drier	Make sure the air filter is clean and indoor airflow is unobstructed; Confirm the outdoor unit is clear of snow and debris; Turn the system off at the breaker for a few minutes, then restore power once
P3	IDS / BOVA central inverter: compressor over-current protection (the compressor is drawing more current than allowed). NOTE: on Climate 5000 ductless units, P3 means outdoor low-temperature lockout pro repair	Compressor mechanical/electrical overload; Restricted airflow raising system pressures and load; Refrigerant overcharge	Clear any obstruction around the outdoor unit and make sure the indoor filter is clean; Turn the system off at the breaker for several minutes, then restore power once
P4	IDS / BOVA central inverter: high compressor discharge temperature protection (T5) – the discharge line is too hot pro repair	Low refrigerant charge; Restricted airflow or dirty coils; Faulty metering device / expansion valve	Make sure the air filter is clean and indoor airflow is unobstructed; Clear debris from the outdoor coil; Turn the system off at the breaker for several minutes, then restore power once
P5	IDS / BOVA central inverter: condenser-coil temperature protection (T3) in cooling – the outdoor coil is running too hot in cooling mode. NOTE: on Climate 5000 ductless units, P5 means a multi-zone mode conflict pro repair	Dirty or blocked outdoor (condenser) coil; Outdoor fan not running or restricted; Recirculation of hot air around the unit	Clear leaves, snow and debris from the outdoor coil and around the unit; Make sure nothing is restricting airflow over or around the outdoor unit; Turn the system off at the breaker for a few minutes, then restore power once
P8	IDS / BOVA central inverter: DC fan motor 'hurricane/typhoon' protection – high wind is force-spinning the outdoor fan, so the unit limits/protects the fan motor pro repair	High wind spinning the outdoor fan blade backwards or faster than commanded; Failed or noisy DC fan motor feedback	In high-wind weather this can be temporary – allow the unit to resume once winds calm; Confirm the outdoor fan is clear of debris; Turn the system off at the breaker for a few minutes, then restore power once
PH	IDS / BOVA central inverter: low discharge superheat protection (the compressor discharge superheat has dropped too low, indicating possible liquid refrigerant return) pro repair	Refrigerant overcharge; Metering device / expansion valve overfeeding; Low load conditions	Make sure the air filter is clean and airflow over both coils is unobstructed; Turn the system off at the breaker for a few minutes, then restore power once
F1	IDS / BOVA central inverter: IPM (inverter power module) protection – the inverter module has reported a fault. NOTE: on Climate 5000 ductless units, F1 means outdoor ambient sensor error pro repair	Inverter / IPM power module overheating or failure; Compressor fault drawing excessive current; Low or unstable supply voltage	Clear any obstruction around the outdoor unit so it can cool properly; Turn the system off at the breaker for several minutes, then restore power once
L0-L9 (AtL)	IDS / BOVA central inverter: 'Ambient temperature Limited' – the unit is intentionally limiting (derating) compressor output because the outdoor ambient temperature is outside the optimal band. This is a protective limit, not a hard failure; the unit keeps running at reduced capacity DIY-checkable	Very high or very low outdoor ambient temperature; Normal protective derating during temperature extremes	This usually clears on its own as outdoor temperatures moderate – no action is needed in extreme weather; Confirm the outdoor unit is clear of snow and debris
dF	IDS / BOVA central inverter: 'dF' indicates the outdoor unit is in a normal DEFROST cycle (it is melting frost off the outdoor coil in heating mode). This is normal operation, not a fault – heating pauses briefly and steam may rise from the outdoor unit DIY-checkable	Normal frost build-up on the outdoor coil in cold, damp weather triggers an automatic defrost	No action needed – allow the defrost cycle to finish (typically a few minutes) and heating will resume automatically
L / D / P / F / C / U / A (status letters)	IDS / BOVA central inverter: when the first character on the control-board LED is one of these letters (followed by two digits showing compressor frequency in Hz), the unit is RUNNING in a limited/derated condition, not failed: L = limited by T3 (coil temp), D = limited by T5 (discharge temp), P = limited by compressor ratio, F = limited by TF (module temp), C = limited by current, U = limited by low voltage, A = oil-return mode DIY-checkable	Normal protective derating near operating limits (temperature, current, voltage) or during a periodic oil-return cycle	These indicate the unit is protecting itself while still running – usually no action is needed; Confirm both coils have clean, unobstructed airflow (clean filter, clear outdoor unit)

Bosch heat pump codes we get called for most

E0 — Climate 5000 ductless: indoor unit EEPROM error (the indoor control board's memory chip could not be read/written correctly)

Typical causes include indoor control board (pcb) fault or corrupted eeprom; power surge or brown-out during operation; loose connector on the indoor pcb. A few things are safe to check yourself (Turn the system off at the breaker for a few minutes, then restore power once to allow a fresh start-up), but the repair is a licensed HVAC technician job. HeatLand diagnoses and fixes E0 on Bosch heat pumps throughout Greater Vancouver.

E4 — Climate 5000 ductless: indoor return-air temperature sensor error (the room-air thermistor is open or short circuited)

Typical causes include failed room-air thermistor; loose or damaged sensor harness/connector on the indoor pcb; indoor control board fault. A few things are safe to check yourself (Turn the system off at the breaker for a few minutes, then restore power once; Confirm the indoor unit's air intake is not blocked), but the repair is a licensed HVAC technician job. HeatLand diagnoses and fixes E4 on Bosch heat pumps throughout Greater Vancouver.

F1 — Climate 5000 ductless: outdoor ambient temperature sensor error (the outdoor air thermistor is open or short circuited). NOTE: on IDS/BOVA central units, F1 means something different – IPM module protection

Typical causes include failed outdoor ambient thermistor; loose or corroded sensor connector on the outdoor pcb; outdoor control board fault. A few things are safe to check yourself (Turn the system off at the breaker for a few minutes, then restore power once; Confirm the outdoor unit is not obstructed), but the repair is a licensed HVAC technician job. HeatLand diagnoses and fixes F1 on Bosch heat pumps throughout Greater Vancouver.

EC — Climate 5000 ductless: low refrigerant detected (the system has sensed a refrigerant shortage / possible leak)

Typical causes include refrigerant leak in the lineset, coil, or flare connections; undercharge from improper installation; faulty sensor logic on a low-charge system. A few things are safe to check yourself (Confirm the outdoor unit is clear of snow, leaves and debris and that airflow is unobstructed; Make sure the indoor filter is clean), but the repair is a licensed HVAC technician job. HeatLand diagnoses and fixes EC on Bosch heat pumps throughout Greater Vancouver.

Is it safe to keep running a Bosch heat pump with a fault code?

Most Bosch fault codes put the heat pump into a safe lockout for a reason. You can safely check the basics — the power and breaker on, the indoor filter clean, the outdoor unit clear of snow, ice and debris, and the remote set to the correct mode and temperature — and restart it once. If the code returns, stop and book a technician. Mini-split and heat-pump faults are electrical and refrigerant issues — never open the indoor or outdoor unit, and never touch the wiring or refrigerant lines yourself.

Bosch heat pump repair across Greater Vancouver

HeatLand has kept Metro Vancouver homes comfortable since 1999. Our licensed, insured technicians diagnose and repair Bosch heat pumps — sensor and thermistor errors, indoor-to-outdoor communication faults, fan and compressor problems, refrigerant and pressure faults, and control-board issues — including units we didn’t install. We’re brand-agnostic, carry common parts, and give you an honest repair-or-replace assessment with upfront pricing and a free estimate. If your heat pump is beyond economical repair, we’ll show you right-sized, high-efficiency replacement options and the rebates available.

Need it sorted fast? We offer priority emergency heat pump repair. Explore Heat Pump services, browse all heat pump error codes by brand, or request a free estimate.

Bosch heat pump service areas

We repair Bosch heat pumps across Greater Vancouver and the Fraser Valley, including:

Bosch heat pump error code FAQs

Can I reset my Bosch heat pump myself?

Yes — power-cycling the unit at the breaker once is generally safe after you’ve checked the basics (the power and breaker on, the indoor filter clean, the outdoor unit clear of snow, ice and debris, and the remote set to the correct mode and temperature). If the heat pump faults again right away, stop and note the code — repeatedly resetting a heat pump that keeps locking out can mask a real problem. Call a licensed HVAC technician to diagnose it.

What does the Bosch E1 code mean?

On Bosch heat pumps, E1 commonly indicates climate 5000 ductless: communication error between the indoor unit and the outdoor unit (no valid data is being exchanged over the interconnecting cable). one of bosch's most common climate 5000 codes. Confirm the exact meaning against your unit’s manual — codes can vary by model and series — and have the repair done by a licensed HVAC technician. HeatLand fixes this across Greater Vancouver.

Do you repair Bosch heat pumps you didn’t install?

Yes. HeatLand is brand-agnostic and services Bosch heat pumps throughout Metro Vancouver and the Fraser Valley, whether or not we installed the unit. We carry common parts and give you an honest repair-or-replace assessment.

Is a Bosch heat pump fault code an emergency?

No heat in cold weather or no cooling in a heat wave is worth treating urgently. For priority heat pump repair across Greater Vancouver, call (604) 330-3812.

How much does Bosch heat pump repair cost in Vancouver?

It depends on the fault. Many Bosch codes point to sensors, thermistors, capacitors or control parts — usually far cheaper than replacement. We give upfront pricing and a free estimate before any work.

More Heat Pump error-code guides

HeatLand repairs every major heat pump brand across Greater Vancouver. More brand guides: