Dovecot on CentOS 7

I guess I've been lucky. My Red Hat server I built in 2003 finally gave up the ghost yesterday. Fifteen years with almost zero problems running 7x24. Now I'm trying to build a basic server to host my e-mail using CentOS 7, Sendmail and Dovecot. Server is running great as are Sendmail and Dovecot but Dovecot only allows connections from the CentOS 127.0.0.1. I can telnet localhost pop3 and get a +OK Dovecot ready response. Trying to telnet from a different computer on same LAN times out. I've looked at my old Dovecot config files to see how I enabled LAN IP access but the configs have changed a lot since I last installed Dovecot. Googling hasn't helped. Anyone help with a sample config with LAN IPs permitted?