the blue dial is inside the varistream on the circuit board, you have to unscrew it, and start from one side full lock and gently turn it then turn on the varistream with the pole connected until it works, but turning off before adjusting, then disconect/shut off the hose and turn it on and make sure the varistream stops and starts briefly before stopping again, so that means its set right. Take a bit of fiddling. Thats the advantage of the digital one - you can adjust the pressure settings from the main exterior controls, so no need to unscrew it and take it apart.