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: Testing and Inspection

1. Check valves should be inspected whenever the hose is disconnected from the valve or check valve failure is suspected.

NOTE: Any indication of exhaust gases in the air pump indicates check valve failure.

2. Orally blow through the check valve (toward air manifold) then attempt to suck back. Flow should be toward air manifold only.

3. When replacing a check valve, be careful not to bend or twist the air manifold.