California Code, Code of Civil Procedure - CCP § 712.030

(a) Upon delivery of the writ of possession or sale to the levying officer to whom the writ is directed, together with the written instructions of the judgment creditor, the levying officer shall execute the writ in the manner prescribed by law.

(b) The levying officer may not levy upon or otherwise seize property under the writ after the expiration of 180 days from the date the writ was issued.