The Radionics (now Bosch) control panels were good robust Panels, but none of them were DIY-friendly; so I wouldn't count on ever being able to reprogram any of the settings, e.g., deleting a zone. Panel programming requires a special programmer and, depending on the revision number of your panel (before, during, or after 1992), might require a specific dealer code within the programmer to access your particular Panel.
Think in terms of either physically fixing the zone loop, or jumping it out. It's usually not that hard to do.
If you look on the terminal strip along the bottom of the Control Panel in its steel cabinet (
not the Keypad), you'll find Terminals 16 thru 28 holding the zone loops for Zones a through h. Those zones are
nearly always programmed as Zones 1 thru 8, with a=1 and h=8.; so Zone 8 is
probably landed on Terminals 27 and 28.
The Zone 8 loop from the Panel to the mag switch(es) on the window(s) has a 1000-Ohm (1 KΩ) resistor somewhere in series with the magnetic switch (aka "contact") on the window, called an End-of Line Resistor (EOL), because the manufacturer prescribes placement at the last switch in the zone loop, so that the loop is supervised. If there is only one window switch/contact on Zone 8, then that is the end of line switch. However, most installers don't consider it necessary to place the resistor at the end of the line in residential installations, so chances are that the EOLR is landed on Terminal 27 or 28 on the Panel. You'll have to look to find it.
Once you've located the 1 KΩ EOLR--it will have color-coded bands, brown-black-red-gold---disconnect the wire pair (the loop) from T27 & T28, and use the resistor as a jumper from T27 to T28. Note that Zone g shares a common ground/negative terminal, T27, with Zone h, and be sure to leave the Zone g wire in place.
All that being said: It might actually be easier to
fix Zone 8 than to jump it. A fair percentage of open magnetic switches go open because their paired magnet is missing---either fell or been knocked off; or has become misaligned. Fixing it might be as simple as replacing or re-positioning the magnet. I'd have a better idea if I could see a picture of the switch/contact on/in the window.
EDIT: Almost forgot: Here's a link to the D6112 User Manual.
http://www.nationalsecuritysystems.net/user guides/radionics/d620.pdf
IF the installer enabled Selective Zone Shunting in Panel Programming, you'll find instructions on page 23 to shunt (bypass) a zone at the keypad. But be aware, you must go through the procedure each time you arm the system. There is no keypad command to permanently shunt a zone.
