Caldera Spa Heater Relay Board Item #: 74618 Description: Caldera Spa Heater Relay Board used in the Advent Control Box 2002 to 2008 Paradise and Utopia Models. Comes with Jumpers and Shortened Screws for The Front CoverUsed on Caldera, Hot Springs, Tiger River and Lime Light Spas Fits the following Caldera models: Kauai Geneva Elation Niagara Hawaiian Martinique Kauai Tahitian Aspire What are the symptoms this part has failed? No power going to the heater even though the red HTR ON L.E.D. light is lit inside the IQ2020 control box. The heater board is charred on the front and/or the backside. Note: There are 2 jumpers included with this board for the Hot Springs Spas that are not needed for the Caldera Spas both spa lines manufactured by Watkins.