Rebuilding the Electrical and Water-Supply Side of a Pump-Fed Sprinkler System in St. Clair Shores, Michigan

Pump-fed irrigation systems have more moving pieces than a typical city-water sprinkler system. A failure can occur in the controller signal, pump-start relay, line-voltage wiring, pump motor, suction plumbing, intake, mainline, valves, or individual zones.

Hunter HydroTech completed an extensive pump-system repair in St. Clair Shores, Michigan that required work on both the electrical path to the pump and the water-supply path feeding the sprinkler system.

A repair that extended well beyond one sprinkler head

The project required excavation and reconstruction in several parts of the irrigation system. Hunter HydroTech trenched approximately 50 feet, with the excavation reaching roughly two feet wide and two feet deep in the work area, to establish a new protected path for wiring between the pump-start relay and the pump.

The overall repair included:

• New conduit between the pump-start relay and pump
• New wiring through the conduit
• Pump-start relay and pump wiring work
• Replacement work on the intake and suction side
• Mainline repairs
• Valve repairs
• Individual zone repairs
• Replacement of damaged or failed sprinkler heads

Why the pump-start relay and pump wiring matter

In a pump-fed sprinkler system, the irrigation controller does not simply send full pump power through a station terminal. The controller provides a low-voltage signal to a pump-start relay. The relay then controls the separate power circuit that operates the irrigation pump.

A dependable system therefore requires both sides to work correctly:

• The controller must send the correct low-voltage pump signal
• The relay must respond correctly
• The power circuit to the pump must be intact
• The pump motor must receive the proper supply
• The wiring must be protected appropriately for its location

Installing new conduit and wiring created a defined, protected route between the relay and pump rather than leaving a questionable electrical path in service.

The pump can run and still fail to deliver water

Electrical operation is only half of a pump-fed irrigation system. The pump also has to pull water successfully through its intake and suction piping.

A suction-side problem can cause symptoms such as:

• Loss of prime
• Air entering the pump
• Weak or unstable sprinkler pressure
• A pump that runs without moving the expected amount of water
• Long prime times
• Repeated loss of water between cycles

On this St. Clair Shores project, Hunter HydroTech replaced the intake/suction side as part of restoring dependable water delivery to the irrigation system.

Why suction plumbing has to remain airtight

A discharge-side leak normally pushes water out. A suction-side leak can pull air in. That distinction is important because a small air leak may prevent the pump from maintaining prime even when very little water is visible around the connection.

The foot valve, screen or intake assembly, suction piping, fittings, check components, and pump connection all have to work together to keep the pump supplied with water.

Restoring the system after the pump supply was addressed

Once the pump can receive power and move water, the irrigation distribution system still has to carry that water through the mainline, valves, zone piping, and sprinkler heads.

This project also required mainline, valve, zone, and sprinkler-head repairs. That is common on neglected or aging pump-fed systems: fixing the pump may reveal additional leaks or weak components that were hidden when the system could not build pressure.

Why pump systems should be diagnosed in order

Replacing parts randomly on a pump system can become expensive quickly. Hunter HydroTech approaches the system as a sequence:

1. Controller command
2. Pump-start relay response
3. Power to the pump
4. Pump mechanical operation
5. Prime and suction integrity
6. Discharge pressure
7. Mainline integrity
8. Valve operation
9. Zone flow and sprinkler coverage

Working through that sequence helps separate an electrical problem from a suction problem, and a pump problem from a downstream sprinkler-system problem.

St. Clair Shores pump-system repair

Hunter HydroTech provides irrigation pump-system repair, pump-start relay troubleshooting, suction-line repair, intake service, valve repair, mainline repair, and sprinkler-zone troubleshooting throughout Southeast Michigan.

See our St. Clair Shores irrigation service page and St. Clair Shores pump-system repair page for local service information.