Bosch Compress Hd fault code
Bosch Compress heat pumps
What the Bosch Compress Hd fault code means, from the manufacturer's own service literature, and the UK models it applies to.
What it means
Communication error between master and slave units
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 Hd on that machine.
Outdoor units37
Hd 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
Hd 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 Hd 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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