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Jet Pump Troubleshooting

This “TROUBLESHOOTING” information is intended to guide in the general determination of pump problems and their solutions. Each manufacturer normally provides a description of warranty conditions. Some pump warranties are immediately voided if the unit is disassembled. Be sure to thoroughly read the owner's manual and warranty. Installation and Repairs Disclaimer: Installation and parts manuals are provided only as reference tools. Seller makes any representation or warranty of any kind to the Buyer that he or she is qualified to neither install nor make any repairs to the product. Seller expressly states that installation, repairs and parts replacements should be undertaken by competent and qualified persons, technicians or contractors and not by the Buyer. The Buyer assumes all risk and liability arising out of his or her installation or repair to the original product.
Note: There may be system problems caused by auxiliary controls not covered here.

Pump Will Not Run or Start

  • Blown fuse or power turned off: Check to see if fuse is OK. Check power. If blown, replace with fuse of proper size. Turn power on.
  • Low line voltage: Use voltmeter to check pressure switch or terminals nearest pump. If voltage under recommended minimum, check wire size from main switch on property. If OK, contact power company.
  • Loose, broken or incorrect wiring: Check wiring circuit on diagram. See that all connections are tight and no short circuits exist because of worn insulation, crossed wire, etc. Rewire any incorrect circuits. Tighten connections, replace defective wires.
  • Defective motor: Check to see that switch is closed. Repair or take to motor service station.
  • Defective pressure switch: Check switch setting. Examine switch contacts for dirt or excessive wear. Adjust switch settings. Clean contacts with emery cloth if dirty.
  • Tubing to pressure switch plugged: Remove tubing and blow through it. Clean or replace if plugged.
  • Impeller or seal: Turn off power. Using a screwdriver, try to turn impeller or motor. If impeller will not turn, remove housing to locate source of binding.
  • Defective start capacitor: Use an ohmmeter to check resistance across capacitor. Needle should jump when contact is made. No movement means an open capacitor; no resistance means capacitor is shorted. Replace capacitor or take motor to service station.
  • Motor shorted out: If fuse is blown when pump is started (and external wiring is OK), motor is shorted. Replace motor.

Pump Operates But Delivers Little Or No Water

  • Low line voltage causing reduce motor speed: Use voltmeter to check at pressure switch or terminals nearest pump. If voltage under recommended minimum, check size of wiring from main switch on property. If OK, contact power company.
  • System incompletely primed: When no water is delivered, check prime of pump and well piping. Fill pump completely with water through priming opening and reprime pump.
  • Air lock in suction line: Check horizontal piping between well and pump. If it does not pitch upward from well to pump, an air lock may form. Rearrange piping to eliminate air lock.
  • Undersized piping: If system delivery is low, the piping and/or plumbing lines may be undersized. Refigure friction loss. Replace undersized piping or install pump with higher capacity.
  • Leak in air volume control or tubing (Galvanized tank installations): Disconnect air volume control tubing at pump and plug hole. If capacity increases, a leak exists in the tubing of control. Tighten all fittings and replace control if necessary.
  • Pressure regulating valve stuck or incorrectly set (deep well only): Check valve setting. Inspect valve for defects. Reset, clean or replace valve as needed.
  • Leak on suction side of system: On shallow well units, install pressure gauge on suction side. On deep well systems, attach a pressure gauge to the pump. Close the discharge line valve. Then, using a bicycle pump or air compressor, apply about 30 PSI pressure to the system. If the system will not hold this pressure when the compressor is shut off, there is a leak on the suction side. Make sure above ground connections are tight. Then repeat test. If necessary, pull piping and repair leak.
  • Low well level: Check well depth against pump performance table to make sure pump and ejector are properly sized. If undersized, replace pump or ejector.
  • Wrong pump/ejector combination: Check pump and ejector models against manufacturer’s performance tables. Replace ejector if wrong model is being used.
  • Low well capacity: Shut off pump and allow well to recover. Restart pump and note whether delivery drops after continuous operation. If well is “weak”, lower ejector (deep well), use a tail pipe (deep well) or switch from shallow well to deep well equipment.
  • Plugged ejector: Remove ejector and inspect. Clean and reinstall if dirty.
  • Defective or plugged check valve or foot valve and/or strainer: Pull valve and inspect. Partial clogging will reduce delivery. Complete clogging will result in no water flow. A defective valve may cause pump to lose prime, resulting in no delivery. Clean, repair or replace as needed.
  • Worn or defective pump parts or plugged impeller: Low delivery may result from wear on impeller or other pump parts. Disassemble and inspect. Replace worn parts or entire pump. Clean parts if required.

Pump Delivers Water - Will Not Shut Off

  • Impeller worn or plugged, no jet assembly installed, or jet plugged: Install jet assembly or unclog as required.
  • System head too high: If head cannot be changed, replace pump with suitable unit.
  • Suction lift or suction losses excessive: Lower pump and or replace excessive amount of fittings in the line.
  • Pressure switch plugged: Unclog as required
  • Pressure switch clogged: Unclog as required
  • Pressure switch incorrectly adjusted: Adjust maintaining 20 PSI differential
  • Leaks in discharge piping or at home: Repair leaks

Pump Cycles Excessively (Starts & Stops Too Often)

  • Leak in pressure tank: Apply soapy water to entire surface above water line. If bubbles appear, air is leaking from tank. Repair leaks or replace tank.
  • Defective air volume control: This will lead to a waterlogged tank. Make sure control is operating properly. If not, remove and examine for plugging. Clean or replace defective control.
  • Faulty pressure switch: Check switch setting. Examine switch contacts for dirt or excessive wear. Adjust switch settings. Clean contacts with emery cloth if dirty.
  • Leak on discharge side of system: Make sure all fixtures in plumbing system are shut off. Then check all units (especially ball cocks) for leaks. Listen for noise of water running. Repair leaks as necessary.
  • Leak on suction side of system: On shallow well units, install pressure gauge on suction side. On deep well systems, attach a pressure gauge to the pump. Close the discharge line valve. Then, using a bicycle pump or air compressor, apply about 30 PSI pressure to the system. If the system will not hold this pressure when the compressor is shut off, there is a leak on the suction side. Make sure above ground connections are tight. Then repeat test. If necessary, pull piping and repair leak.
  • Leak in foot valve or check valve: Pull piping and examine foot valve. Repair or replace defective valve.
  • Water logged pressure tank: Drain tank. Replace air volume control as needed.
  • Pump farther than 4 feet from tank: Shorten the distance between tank and pump.
  • High friction loss valves between pump and tank: Use only fully open gate valves.

Motor Overheats And Overload Trips Out

  • Incorrect line voltage: Use voltmeter to check at pressure switch or terminals nearest pump. If voltage under recommended minimum, check size of wiring from main switch on property. If OK, contact power company.
  • Motor wired incorrectly: Check motor wiring diagram. Reconnect for proper voltage as per wiring diagram.
  • Inadequate ventilation: Continuous operation at very low pressure places heavy overload on pump. This can cause overload protection to trip. Install globe valve on discharge line and throttle to increase pressure.

Pump Rapid-Cycles

  • Incorrect air charge in tank: Set air-charge 2 PSI below the pump cut-in pressure for steel bladder tanks or 4 PSI for fiberglass bladder tanks.
  • Bladder or diaphragm has ruptured: Check by depressing the air valve stem. If water emerges, diaphragm is ruptured (Replace tank).
  • Incorrect pressure switch differential: Adjust pressure switch differential to 20 PSI. Tank too small. Check tank sizing, (Replace tank).
Notes:
  • Pressure tanks are usually pre-charged at 30 PSI.
  • Drain water from tank to check tank air charge.
  • Pressure switches are usually set for 30-50 PSI.

Pump Axtivates With No Apparent Demand

  • Faulty check or foot valve: Close valve between tank and house. If gauge pressure drops, the check or foot valve is faulty. Replace defective valve.
  • Slow leak in house plumbing: Close valve between tank and house. If gauge pressure does not drop, there is a slow leak in the house plumbing. Repair leak

Tank Loses Air

  • Defective air valve core: Brush soapy water around air stem. If leak is found, the valve core is defective. Replace valve core)
  • Defective tank weld: Brush soapy water around tank welds. If leak is found, the tank is defective. Replace tank.
  • Ruptured tank diaphragm: Replace tank

Water Flow Stops At Cut-in

  • Incorrect air charge in tank: Set air-charge 2 PSI below the pump cut-in pressure for steel bladder tanks or 4 PSI for fiberglass bladder tanks
  • Defective pump: Repair pump
  • Defective well: piping Repair or replace piping.

Tank Won't Fill

  • Incorrect air charge in tank: Set air-charge 2 PSI below the pump cut-in pressure for steel bladder tanks or 4 PSI below for fiberglass bladder tanks.
  • Diaphragm Stuck: If air charge is 2 PSI below cut-in, relieve all air from tank. Run pump through one cycle. If tank fills, diaphragm was stuck. Reset air charge

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