Hydrotek Valve Skips Zones: Pump Prime and Check Valve Issues

Diagnosing Zone Skipping on a Hydrotek 4000 with Deep Well

A 6-zone Hydrotek 4000 system fed by a deep well skips the next zone after the pump is off for a few minutes. The well has two drop pipes (jet pump setup). No check valve exists. Questions: install suction line check valve? Which line? What does the second line do?

Understanding the Jet Pump Setup

The two lines indicate a jet pump: one line pushes water down (pressure line), the other pulls water up (suction line). A foot valve (with built-in check valve) at the bottom of the suction line is essential—it maintains prime and enables the jet action.

Recommended Fixes

1. Replace the foot valve – It's likely worn, allowing prime loss.
2. Install a check valve in the suction line – At the pump end, as backup.
3. Reprogram the controller – If zone skipping persists, the controller may have a timing fault; replace if needed.

The "extra line" is the pressure line for the jet ejector—don't put a check valve there. Focus on the suction line foot valve.