Designed to clean new or almost-new systems, it dissolves or disperses the flux, greases and copper debris which are invariably left in the system after installation.
Sentinel X300 should be circulated for 2-3hrs at operating temperature, or up to 24 hours if circulated cold... but no longer, and the system should be flushed with clean water immediately after use.
Yes it MUST to be flushed out otherwise all the contamination will remain in the system.
It is fine to use with plastic components. In fact, all Sentinel products have been extensively tested for use with systems having common plastic components.
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