Hayward Super Pump VS 700 Not Starting: How to Diagnose a Dead Motor

What "Not Starting" Actually Means

Before diving into the motor, make sure you have correctly identified the symptom. A pump that is completely silent with no vibration, no hum, and no display activity (on VS models) is a different problem from a pump that hums for a few seconds and then trips, or a pump that displays an error code and refuses to run. This article focuses on the completely dead pump — no response at all.

On variable speed models with a display panel, also check whether the display is showing anything. A blank display but active power suggests a drive or display board failure. A display showing an error code should be resolved using the error code guide rather than this article.

Step 1: Check the Circuit Breaker and GFCI

The most common cause of a completely dead pump is a tripped breaker or GFCI. The NEC requires pool pump circuits to be protected by a GFCI breaker, and GFCI breakers trip on very small ground current imbalances — sometimes due to a genuine fault, and sometimes due to nuisance conditions like moisture in a conduit.

1. Go to the main electrical panel. Locate the breaker for the pool pump circuit.
2. A tripped breaker usually shows a position between ON and OFF, or an orange indicator window. Push it fully to OFF before resetting to ON.
3. If the breaker is a GFCI type, press the TEST button — the breaker should trip. Press RESET. If it holds, the breaker itself is functioning correctly.
4. If the breaker trips immediately on reset, stop. Do not keep resetting a breaker that trips immediately — this indicates a hard fault that must be diagnosed before restoring power.
5. Also check any sub-panels, time clocks with integral breakers, or GFCI outlets in the equipment area that may be in the circuit.

Step 2: Bypass the Timer

Many pool pumps run on a mechanical or digital timer that may not be calling for the pump during your visit. Before assuming a hardware failure, confirm that the timer is actually telling the pump to run.

1. Locate the time clock or automation controller that schedules the pump.
2. On a mechanical timer: manually rotate the tripper arms so that the "ON" period covers the current time, or place the override lever in the ON position.
3. On a VS pump with an internal scheduler: confirm the pump day-of-week and time-of-day settings are correct. A wrong day or reversed AM/PM will prevent any programmed run from occurring.
4. If the pump starts when the timer is bypassed or manually commanded, the problem is in the schedule, not the pump hardware.

Step 3: Inspect Terminal Connections in the Junction Box

Loose or corroded wiring connections inside the motor junction box are a common cause of intermittent or total failure to start. Pool environment humidity causes corrosion, and vibration over years of operation can loosen screw terminals.

1. Turn off the breaker. Verify power is dead using a non-contact voltage tester at the conduit entering the motor.
2. Remove the junction box cover — typically held by two screws on the top of the motor.
3. Check that all terminal screws are tight. Loose connections create high resistance that prevents the motor from drawing enough current to start.
4. Look for corrosion (green or white buildup) on terminals or wire ends. Corroded connections must be cleaned or the wires cut back to bare copper and re-terminated.
5. Verify the wiring configuration matches the motor nameplate diagram. The Super Pump VS 700 must be wired for the available field supply voltage — mismatched wiring (e.g., 240V wired as 120V or vice versa) will prevent starting or damage the motor.
6. Also verify the ground terminal is securely connected and the bonding wire is attached to the external bonding lug on the motor housing.

Step 4: Check Motor Shaft for Free Movement

If power is confirmed at the motor but it still will not start, check whether the motor shaft is physically able to rotate. A seized impeller or jammed wet end will prevent the motor from turning — the thermal overload will trip before any damage to the windings if the motor was running, but if the obstruction occurred while the pump was off, the motor may not be able to develop enough starting torque to break free.

1. Turn off the breaker.
2. Remove the motor end cover — typically held by two screws. On TEFC (totally enclosed fan-cooled) motors, the shaft is accessible through the fan shroud without removing the end cover.
3. Using a flat-blade screwdriver, 1/4" hex driver, or 7/16" wrench on the motor shaft (refer to the manual for your specific motor type), attempt to rotate the shaft by hand.
4. The shaft should rotate with moderate effort. Resistance to rotation is normal; complete inability to rotate indicates a seized impeller, debris in the pump housing, or seized bearings.
5. If the shaft is jammed, open the wet end: remove the four 3/8" x 2" housing cap screws, slide out the motor assembly, and inspect the impeller for debris such as leaves, hair, or small stones.
6. Remove the obstruction. If the impeller itself is damaged or the motor bearings are seized, the component must be replaced before attempting to restart.

Step 5: Verify Supply Voltage

The Hayward manual specifies that supply voltage must be within 10% of the motor nameplate voltage when running at full load. Voltages outside this range prevent reliable starting and trigger thermal overload. Undersized wiring is the most common cause of low voltage at the motor — especially on longer runs from the panel.

1. Restore power at the breaker.
2. Using a voltmeter, measure the supply voltage at the motor junction box terminals with the pump in the off state (before starting).
3. Command the pump to start (via the display or timer) while monitoring the voltage. Note whether voltage drops significantly during startup — a drop of more than 10% indicates undersized wiring or a weak supply.
4. For a 240V nameplate pump, supply voltage should stay between 216V and 264V. For a 120V pump, it should stay between 108V and 132V.
5. If voltage is out of range, contact a licensed electrician to evaluate the wiring gauge and service capacity. Do not attempt to run the pump on an out-of-spec supply.