In my spa I have a United Spas 3A heater and a len Gordon digital side control. The timer in the 3A controls the low speed pump only. The heater is controlled by the digital side control. The two operate independently.

The problem is that if the timer calls for the low speed pump to turn off, the heater can still turn on and when it does there is no water movement and the high limit switch is tripped on the heater.

I would like the heater and the low speed pump to turn on and off at the same time.

How do I get them to do this?

Just did some research and I may need to adjust my pressure switch. It is currently turned all the way out for some unknown reason and I think I need to turn it in until it shuts off the heater then out ~1.5 turns.

I'll try it tonight. I would guess this is my problem...if not I'll be back.