bosch greenstar 151 combi wall mounted. zwb42-3

arian_d

hi.
i have a Bosch combi boiler 151p. installed it myself. everything works fine, i just want to know, how to change the priority of domestic hot water. every time i opened the faucet, all 3 zone valves turn off. i have read the manual, it says eco button lit, means it will alternate between hot water and heating system. but if the zone valves are turned off how does it achieve that?
i have the combi boiler installed with bosch zone controller czm100, and 3 zone valve. with 3 bosch thermostat crc200.
how can i keep at least one zone running wile hot water is being used in the kitchen sink?
thank you all.