Looks like a finnex heater from his earlier posts. A lot of brands can malfunction, I’ve had Cobalt in the past and they have been great for me, but when a heater goes it’s bad regardless of brand. This is why Randy from BRS always pushes for replacing them every year as the hearing elements get so much wear on them from all of the on/off commands.
Let me guess it was a colbolt neotherm heater.