Bosch 1001

Medium

Compress / Logamatic EMS plus — No communication between system controller and remote control (room sensor shows A21/A22/A23/A24 depending on heating circuit).

Bosch 1001: No communication between system controller and remote control (room sensor shows A21/A22/A23/A24 depending on heating circuit). This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Poor EMS connection between display and installer module.

Check steps

Check both ends of EMS cabling between the boards.

Affected parts

EMS-Kabel

Safety note

Isolate power before testing.

Source: Bosch Alarm List A/W Split (8754), 2018-01-10, official Bosch heat pump alarm list (distributed via lvisawo.fi)

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

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