Sbates

I have a hot springs sovereign 2001. We just replaced the heater and the heater relay board. Before replacing the heater relay board all was working except heating up to temp. It was warm but not hot. After replacing the relay board now we have a red light on the circuit board on that we don’t know what it means. The red heater light on the circuit board does not come on. This red light is located about in the center of the circuit board. Can you please help!!