Power flushing is done at high pressure
Power flushing is done at high flow rates (around 100 liters per minute) but at low pressure. It’s actually done at much lower pressure than sealed systems normally operate under.
Power flushing happens at around 1.0 bar, whereas your system can be pressurized to up to 3.0 bar (not that it should), and normally operates at around 1.5bar.
For open vented systems, the pressures are nearly the same. It's actually a very safe and effective procedure, if done by a professional.
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