I purchased an ECO-7 topside control 7/10/07. I wasn't given a manual with the control. I am running a Hydro-Quip 6200 solid state control unit. The heat stopped working and there are 3 dots blinking on the control. Half second on, half second off. This started happening several months ago and would generally go away if I turned the power off and back on at the circuit breaker. Now, however, the blinking won't go away and the heat won't come back on. The pumps and jets work fine. The heater light on the control unit does not light up. What could the problem be?

When you reset the tub, do the dots show up before the pump comes on? Is the temp display accurate?

If your answer is yes to both of those, you either have a "Flow Closed" error (your pressure switch is closed when the pump is off) or a bad High Limit sensor.