parva he boiler m96.28sm/p won't heat radiators?

my parav he m96.28sm/p boiler heats the water from tap but not the radiators.
it had been reset by accidfent a few hours earlier while trying to get it to heat at set times. i tried to make use of the manual and managed to get the far left lamp to go from 4 second gap flashes to 1 second gap flashes which then activated the red lock light to flash at 1 second intervals but that's it. if i adjust the dials it goes back to how it first was flashing.
how do i get it to heat the rads and control from thermostat on wall again please?