Hello-drained and refilled tub now heat relay on 2004 CalSpa CS5000 will not close allowing no heat. Heat Element tested positive for resistance, pressure switch, temperature and high limit sensors are good. Pumps are working fine. Same situation several years ago but miraculously fixed itself after 4 days of cycling on and off. Happened again last year but it was a bad pressure switch.
Is it circuit board replacement time (: