How to Wire Above Ground Pools

Wiring an outdoor, above-ground pool requires forethought and planning. There are three main circuits to consider: pool pump, pool heater and lighting. An above ground pool usually requires a low horsepower, low head-pressure pump, that can run on 110 volts. Pool heaters are available in either gas fired or heat pump. Gas fired heaters have a very low amperage need, usually 0.05 amps, and can draw power from the pool pump circuit. A heat pump operates at 220 volts and needs a dedicated power line. Lighting for the pool can use low-voltage systems, but needs 110 volts to power the low-voltage transformer.

Wire nuts are required by national code
  1. Dig a trench from the power supply location (usually the garage) to the pool location. Check local codes for the trench depth and bury three cables; one rated 10-3, the other two 14-3. The heavy gauge cable (10-gauge) is for a heat pump. The lighter duty 14-gauge will power the water pump and lights. These wires are commonly called Romex wire. If local code permits, Romex is available in a direct-bury form and does not need to be enclosed in conduit.

  2. Install conduit from the buried cable to the circuit breaker panel. Open the panel door and shut down all power to the breakers. Remove the breaker cover. Run the wire from underground, through the conduit and into the panel (the control panel will have a knock-out on the side). Remove it to allow the conduit connector along with the wiring through the panel. Secure the connector to the panel and run enough wire to easily route and install it to new circuit breakers.

  3. Dig a hole deep enough to anchor a support pole according to local code. Anchor the pole with a bag of premixed concrete. Attach outdoor, weatherproof switch housings for each circuit that is needed. Run conduit from the trench to the switches. Insert the wire through the conduit and into the switch housings. Local code may require the support pole be located a specific distance from the pool. Follow all code requirements.

  4. Wire the circuit breakers in the breaker panel. Insert two new 110-volt, 15-amp circuit breakers into the panel. Install a black light gauge wire into the 15-amp circuit breaker and tighten the retaining screw. Attach a white wire to the common buss-bar. Install the green wire to the ground bar. Insert a new, 220-volt circuit breaker rated at the amperage requirements of the heat pump. Insert a black and white wire into the breaker and tighten the leads. Install the green wire to the ground bar. There is no neutral connection since the heat pump is a direct-connect device.

  5. Set the water and heat pump on a concrete or brick pad. Local codes may have minimum requirements. A low-voltage outdoor light transformer can be secured directly to the switch post. Run conduit from the outdoor housings to the pump and heater. Run the appropriate size wire from the switch housing to each component.

  6. Wire the components. The pool pump may be installed in conjunction with a timer. Follow the manufacturer directions and attach the timer to a 110-volt power supply. Attach the low-voltage transformer wires directly to a 110-volt power supply as well. Use wire-nuts to connect all wires, and cover each housing with a watertight, weatherproof housing cover. Directly connect 220-volts to the heat pump. Do not include an on-off switch. Connect these wires in the post mounted housing and install a sealed cover, and then cover all the trenches.