The following pictures below demonstrates how to remove the Irritrol or Hardie Rain Dial RD-600 / 900 / 1200 & "R" series timer from the gray protective wall unit – no tools, no electrical issues, no re-wiring necessary for this procedure.
1. Unlatch the controller from the gray protective wall unit and unplug the 16 or 20 pin black connector from the 24VDC circuit board. Gently pull the black connector from the circuit board and try not to damage the gray ribbon cable!!!
2. Swing open the controller and pull the controller out of the two snap-in hinges. Pull straight from the top hinge, then from the bottom hinge. Do not "gorilla" the controller out of the weather proof case.
3. Now simply mail the controller, using the "free" US Post Office flat rate box, to Rain Dial Exchange for a refurbished timer unit. The flat rate USPS box fits the Irritrol / Hardie timer perfectly and about $6 to ship anywhere in the U.S. Usually, the post office has these boxes next to their ATM postage machines.