Flooded Well Pit, Short Cycling, and Air in the Lines
A homeowner has a shallow-well jet pump installed in a below-grade concrete pit. After heavy rain, the pit holds 8 inches of water. The pump short-cycles every 20 seconds, the pressure gauge swings from 38 to 58 psi, and faucets sputter air. The pressure tank is a 42-gallon bladder type; when tapped it sounds hollow at the top and solid at the bottom. The well casing terminates 6 inches below the pit floor, and the pit cover is missing. The pump suction line has a foot valve. The homeowner wants to know if they can just add air to the tank.
1. Identify the immediate safety and regulatory problems. What should be done first?
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The flooded pit is an electrocution and shock hazard because the pump, switch, and wiring are below grade in standing water. The missing cover makes it a fall and confined-space hazard. The well casing terminating below the pit floor is also a contamination and well-construction problem; the wellhead should be above grade, sealed, and graded to drain away from the casing. First, de-energize the circuit at the main panel and do not enter the pit. Treat the pit as a confined space and arrange for safe pumping or removal of water only after power is locked out. A licensed well contractor should raise the wellhead or convert to a pitless adapter, abandon the pit, and correct the electrical installation to weatherproof above-grade equipment. Permits and inspection may be required.
2. Diagnose the short cycling and air sputtering. Why is adding air to the tank not a complete fix?
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A 20-second cycle with a 42-gallon tank indicates very little usable drawdown. The tank may be waterlogged from a failed bladder or lost precharge, but the sputtering also points to air entering the suction side, such as a leaking foot valve, a suction-line leak, or a low water level. The tap test suggests water in the lower tank and possibly a failed bladder. Adding air may temporarily raise pressure, but if the bladder is ruptured, the air will escape into the water and the problem will return. A leaking foot valve can also cause the pump to cycle when there is no demand. The correct approach is to isolate the causes: shut off the pump, drain the tank, check precharge and the air valve for water, pressure-test the suction line, and inspect the foot valve and water level.
3. Outline the repair sequence and the compliance steps you would recommend.
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Lock out and tag out power, then make the pit safe. Replace the failed tank or bladder and set the precharge 2 psi below cut-in. Inspect and replace the foot valve if it leaks, pressure-test the suction line, and repair any air leaks. Verify the well yield and pumping level so the pump does not pull air. Bring the wellhead above grade with a proper sanitary seal and drainage away from the casing; install a pitless adapter if the pit is to be abandoned. Replace missing covers and move electrical controls above grade in weatherproof enclosures. Confirm permits, inspection, and water-quality testing as required. After repairs, record pressure-switch settings, tank precharge, cycle time, and flow before returning the system to service.