Display shows E12 and unit indicates high inlet pressure or error during regeneration start.

Safety first: High pressure can cause leaks or bursts. If you suspect very high pressure, close the main shutoff and contact a plumber if unsure.

• Measure pressure: Attach a pressure gauge to a nearby faucet. Confirm that static pressure is within Crystal Quest's recommended range (typically 40–80 psi). If above, install or adjust a pressure reducing valve on the main line.
• Check for water hammer: If pressure spikes occur when fixtures close, install water hammer arrestors or adjust well pump settings.
• Inspect control head: If your model has an internal pressure sensor, verify its wiring. If E12 persists with normal pressure, replace the Crystal Quest pressure sensor module or main control head as specified.