it will do that if its in engineer mode, check the standby battery in the control panel and the outside bell, they both need to be replaced after 4 years, id have money on either of those dragging down the voltage on the system (should be 13.68v) check the tamper screws on the bell. some bells made by CQR had a a pull up resistor in the installation kit from memory i think it was to stop exactly this type of fault. a 9448 is a very basic panel so it wont be much wrong, check the obvious first, mains power etc.
15 years experience professional fitting
derek
May 2008
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