Jet pump loses prime or runs without building pressure

A jet pump only works when its housing and suction line are full of water. Lost prime almost always traces to an air leak on the suction side, a leaking foot valve or check valve, a clogged foot-valve screen, or a well that has drawn down. Fix the cause, then re-prime; repeated priming alone just burns pumps.

Cross-checked ~60 min moderateBrands: All

Before you start

Turn off the pump breaker before opening the priming plug
Relieve system pressure before opening fittings
Don't let the pump run dry for more than a few minutes

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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