Bosch Compress C0 fault code
Bosch Compress heat pumps
What the Bosch Compress C0 fault code means, from the manufacturer's own service literature, and the UK models it applies to.
What it means
Multiple units configured as master in the master–slave network
Source: Bosch Compress 2000 AWF Installation Manual 6721859133, §12.2 (pp.156-159, render-verified)
UK models this code applies to
Tap yours to open C0 on that machine.
Outdoor units37
C0 on these comes from each model's own manual, which may not match the meaning above — tap yours to read it.
Now the harder half: proving what caused it
C0 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.
Chase C0 on your machine →Free, no sign-up. We don't hold a chart for this code yet — pick the model for its manual section.
Or watch one get chased — free demo →Related codes
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