Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Air Injection Check Valve: Description and Operation

Check valves remain the same as those used in earlier AIR systems. The valves are made of heat and corrosion resistant material. Located in the AIR piping to each bank, check valves prevent exhaust backflow when AIR is commanded OFF or an exhaust backfire occurs.