delete config from LTM

I think these solution would be helpful.

[factory default settings]

sol10519: Restoring the BIG-IP configuration to factory default settings (10.x) http://support.f5.com/kb/en-us/solutions/public/10000/500/sol10519.html

sol13127: Restoring the BIG-IP configuration to factory default settings (11.x) http://support.f5.com/kb/en-us/solutions/public/13000/100/sol13127.html

[clean installation]

sol10819: Performing a clean installation of BIG-IP 10.x or Enterprise Manager 2.x http://support.f5.com/kb/en-us/solutions/public/10000/800/sol10819.html

sol13117: Performing a clean installation of BIG-IP 11.x or Enterprise Manager 3.x http://support.f5.com/kb/en-us/solutions/public/13000/100/sol13117.html

[other]

sol3189: Methods used to dispose of customer data from units returned under RMA http://support.f5.com/kb/en-us/solutions/public/3000/100/sol3189.html