GE 263 - Manual (Page 13)

Water Line Connection 13
Rev A
WARNING: Do not use tools to tighten plastic fittings. Over time,
stress may break the connections. When the 1265 bypass valve is used,
only hand tighten the nuts.
WARNING: Do not use petroleum grease on gaskets when connecting
bypass plumbing. Use only 100% silicone grease products when
installing any Autotrol brand valve. Non-silicone grease may cause
plastic components to fail over time.
WARNING:
Several tube adapters are available to connect the valve
to the water plumbing. See Parts List.