My son-in-law and his wife just moved into a house that has a ADT security system. It's supposed to be hooked to the phone but it's not. It is showing an error for CP and CH. CP is a communication problem cause it's not hooked to the phone line. I don't know what the CH is. Also it's beeping at certain times of the day and night. It started beeping at 8am, then about a week later it changed to beeping at 8pm. Now just recently, it started to beep at 2am. You have to hit "motion" on the control to make it quit beeping. I'll attach a picture of the control panel. The system does have a remote with "on", "off" and "panic". ANY information I can get will help. A side note, there is a transformer on the garage wall that may be part of the system.
Thanks

 

Most likely an Ademco clone and proprietary [useless].

I'd just replace the CPU and keypad and reuse the sensors/wiring.

 

This is an ADT taken over Brinks system. Since ADT bought them, they apparently branded their own name on the keypad models but in either case, these are proprietary as Tpring stated and pretty much useless without the correct programmer and codes.

The CH I believe means "check" and may have a number along with it but again, if you are wanting to use this, you should just replace it and try to salvage any existing wired devices to be reused.

If you found the transformer in the garage that is probably white and has three wire terminals (AC, ground, AC) then that is probably it. You could reuse the wire with a new system and transformer, most likely eliminate the green ground wire.

Unless you were to call ADT and have them reconnect it (along with the fees) then you are better off replacing it or powering it down.