How do I hook up existing ADT home alarm system?
Answers: Unfortunately their systems are designed to only function when they are connected to ADT monitoring systems. They found that empire bought their systems and at end of contract they opt out of monitoring and just used them as you want to. So they put a stop to that.
Just call for them and they will send a tech out.
Heres a tip. Dont post the ADT sign surrounded by your yard.
This tell an experienced burglar what type of security system you hold so he will know what he has to do to disarm it.