I assume you only need to start the pump before the first zone in the program (or do you need to start the pump before every zone in a program)? If you only need to start the pump before the first zone, one solution is to define a dummy zone (it has to be a zone with the smallest index of all other zones: for example, if you have zone 1 as master zone, then use zone 2 as a dummy zone, and your real zones would start from 3 and so on). In a program, give the dummy zone desired amount of time so that it will be the first zone to start, and since it activates the master zone, it will keep the master zone running for that amount of time before moving to the next zone.