Fault Codes / Bosch

99 codes

Compress

• 1037 — Outside temperature sensor faulty — heating standby.
• 1038 — Invalid time/date value.
• 1041 — Voltage failure during screed drying.
• 1051 — No communication with external room temperature sensor.
• 1081 — Two master user interfaces in the system.
• 3081 — Configuration error: remote control.
• 3121 — Temperature limiter (heating circuit) triggered.
• A01 (5201) — Outdoor sensor T1 — open circuit (resistance too high).
• A01 (5202) — Outdoor sensor T1 — short circuit (resistance too low).
• A01 (5204) — Flow sensor T0 — open circuit.
• A01 (5205) — Flow sensor T0 — short circuit.
• A01 (5207) — Heat carrier outlet sensor TC1 fault.
• A01 (5208) — Heat carrier outlet sensor TC1 — short circuit.
• A01 (5213) — Inlet sensor TC0 fault.
• A01 (5234) — Pool temperature sensor TP1 fault.
• A01 (5237) — DHW sensor TW1 fault.
• A01 (5240) — Cooling outlet sensor TK1 fault.
• A01 (5243) — Cooling inlet sensor TK2 fault.
• A01 (5246) — Booster heater limiter (STB) or pressure switch tripped.
• A01 (5265) — Z1 PCB disconnected (CAN bus).
• A01 (5269) — 5269 is NOT a 'flow too low' alarm — it is the electric booster heater (EE) high-temperature cutout on sensor TC1 (>87°C, resets <80°C). Low-flow alarms belong under code 5252.
• A01 (5271) — Flow sensor T0 defective (plausibility).
• A01 (5273) — Z1 phase monitor tripped: one or more supply-voltage phases are missing (compressor control/supply). Check that all phases are present and carry voltage.
• A01 (5294) — Condensation guard tripped.
• A01 (5298) — High pressure alarm (compressor envelope exceeded).
• A01 (5302) — Compressor control system temperature over 110 °C.
• A01 (5310) — Hot gas (discharge) temperature too high.
• A01 (5314) — Discharge temperature sensor TR6 — open circuit.
• A01 (5350) — Compressor control failure – not running / locked rotor.
• A01 (5362) — Z1 overvoltage.
• A01 (5366) — Superheat of discharge gas too low (< 20 K).
• A01 (5414) — Condensate sensor TR3 — open circuit.
• A01 (5420) — Temperature sensor TR4 — open circuit.
• A01 (5426) — Temperature sensor TR5 — open circuit.
• A01 (5432) — Pressure sensor disconnected/faulty.
• A01 (5452) — Internal fault in inverter.
• A01 (5507) — Z1 MR1 high pressure warning.
• A01 (5512) — Compressor outside allowed envelope (>60 s).
• A01 (5523) — Short circuit in inverter (compressor control).
• A01 (5533) — Compressor sensor TR1 — open/short circuit.
• A01 (5547) — Heat source TB0 too low (brine/outdoor).
• A01 (5571) — Brine sensor TB0 — short circuit.
• A01 (5573) — Brine sensor TB0 — open circuit.
• A01 (5577) — Brine sensor TB1 — short circuit.
• A01 (5579) — Brine sensor TB1 — open circuit.
• A01 (5593) — EMS cable not connected or broken.
• A01 (5594) — Z1 air in the system.
• A01 (5902) — Compressor motor overload (overcurrent).
• A01 (5903) — Fault in compressor motor control.
• A01 (5905) — Supply voltage below 180 VAC (undervoltage).
• A01 (5908) — Initialization error of inverter control.
• A01 (5917) — Communication with heating pump PC0 disturbed.
• A01 (5922) — Supply voltage to pump PC0 too high.
• A01 (5923) — Heat carrier pump PC0 reports dry run.
• A01 (5940) — Air in heating pump PC0.
• A01 (5981) — Wrong rotation direction in compressor.
• A01 (5984) — No refrigerant in pump (compressor).
• A01 (5987) — Locked rotor (high motor load).
• A01 (5989) — Phase lost to compressor winding.
• A01 (5993) — Disturbances in Modbus communication.
• A01 (5994) — Low pressure in brine circuit (ground source).
• A11 — No EMS BUS communication / internal connection interrupted.
• A11 (1010) — No communication via EMS BUS.
• A11 (3061) — No communication with heating circuit (mixing module).
• A11 (3071) — No communication with remote/room sensor.
• A11 (3091) — Room temperature sensor faulty.
• A11 (3111) — Configuration error: a room sensor/remote was replaced with a different type (with/without humidity sensor, e.g. CR10 ↔ CR10H) after one had already been learned. Fix: re-run the configuration wizard in the service (commissioning) menu.
• A21 (1001) — No communication system controller ↔ remote control.
• A21 (3141) — Humidity sensor faulty (room sensor).
• A71 (3171) — Low battery voltage in radio room sensor.
• A91 (3181) — No signal from radio room sensor.
• H01 (5252) — Flow at indoor unit restricted.
• H01 (5285) — Risk of frost in heating system.
• H01 (5303) — Z1 temperature too high (compressor protection).
• H01 (5311) — Hot gas temperature too high (TR6 > 110–120 °C).
• H01 (5316) — Discharge temperature sensor TR6 fault (repeated).
• H01 (5331) — Inverter system communication fault.
• H01 (5448) — Expansion valve VR0 — deviation (opened 20% more).
• H01 (5508) — High pressure guard MR1 tripped.
• H01 (5513) — Z1 dew point too high.
• H01 (5524) — Internal error in inverter — replace inverter.
• H01 (5527) — Heat pump overfilled (refrigerant).
• H01 (5918) — Flow < 50 l/h (air in system).

Compress / Logamatic EMS plus

• 1001 — No communication between system controller and remote control (room sensor shows A21/A22/A23/A24 depending on heating circuit).
• 1010 — No communication via EMS BUS connection — the local device hasn't received its EMS token from the bus master for 2 minutes.
• 1052 — No communication with external room temperature sensor module (heating circuit 2) — the installer still has this module selected although it isn't fitted.
• 1082 — Two master programming units in the system — the room sensor for heating circuit 2 has been incorrectly configured as a controller.
• 3061 — No communication with mixer module (heating circuit 1) — a mixing module was previously installed and now the installer module is unable to communicate with the room sensor over the EMS bus.
• 3071 — No communication with remote control (heating circuit 1) — a room sensor was previously installed and now the installer module is unable to communicate with the room sensor over the EMS bus.
• A11 (1037) — Internal program sequence error in control unit.
• A21 (806) — Room temp sensor heating circuit 1 fault — replace remote.
• A21 (816) — No communication with control unit heating circuit 1.
• A41 (1010) — No BUS communication (DHW/storage module).
• A41 (1030) — Internal data error in control unit — replace.
• A41 (4051) — Thermal disinfection failed.
• A51 (812) — Setting error solar module — check parameters.
• A51 (813) — Collector temp sensor — connection line to solar module faulty.
• A61 (1010) — No EMS plus BUS communication — heating circuit 1 module.
• A71 (1010) — No communication mixer/connection module.