Caldera Spas Heater 220 Volt AC, 4.0 kW, 18 Amps - 73994

The heater is a flow through type heater. The heater is powered and controlled by the control box. That is, power is supplied to the heater when the control thermostat determines the spa temperature is too low. The heater is inserted in the discharge of the jet pump plumbing and is located under the control box. The heater is attached to the spa's plumbing using compression fittings at either end.   Specifications: 220 Volt AC, 4.0 kW, 18 Amps   Disconnect power to the spa. Drain the spa. Remove the equipment compartment door. Open the control box lid. Disconnect the pressure switch connection wires from the pressure switch. With two small wrenches of the same size, loosen the nuts that secure the heater connecting bars. Then disconnect the ground wire attached to the heater.