Graco Reactor E-XP1 Troubleshooting Manual page 29

Reactor Error Code Trouble Shooting Guide
 Run the unit to build up pressure (1000 – 1200 psi) with the motor ON
key. When the machine then stalls at set pressure, press the motor OFF
key to clear the E24 warning, but don't depressurize the unit.
Rev 2.6 (02/2014) Page 29