My pump is not turning on when I pull the trigger on my gun, why? 


The Prep Gun Automatic control box allows the high pressure unit to automatically turn the trigger operation on or off.

  • press the gun trigger the motor and pump turns off
  • Release the trigger and the timer will activate.  The motor and pump will shut off as soon as the timer hits the set mark. 


The control works with an ST-6 flow switch.  

  • Minimum pressure for the flow switch is 75 PSI, max 4500 PSI. 
  • Minimum flow rate 1 GPM, max 8.0 GPM


If the switch is not opening when first installed, check the following: 

  • Check the leads and assure power to switch and proper connection
  • Flow rate is less than 1 GPM. Verify water flow rate
  • The magnet is stuck.  Clean the inside housing
  • Reed switch is damaged


You may also check the following if you are still having issues:

  • Socket base:  Make sure none of the terminal wires are loose. Make sure you have power going through the base powering up the timer
  • Control Box: Check the wire in the box to make sure those wires are not loose.  Also check for power 120v/24v
  • MSP(Motor Starter Protector) Is the MSP tripped? if it is, reset the unit.. If it continues to trip, contact an electrician. 
  • Contactor: Is there power going through the wires to activate the contactors. If not, you may have a bad contactor. Contact an electrician. 



Continuously running the motor and pump could potentially wear the pump seals and valves, and damage your motor. The control box is a great way to prevent the motor and pump to prematurely fail. 


If you need any further assistance, please feel free to contact your Sonny's Technical Support team at: sonnyssupport@sonnysdirect.com