I have a 2005 Hotspring Grandee Model G . I have just serviced the spa replacing the filters ( tri-x) with new ones.
Before draining the spa the green light was blinking on the front exterior panel and the water was not coming up to temperature, and so I thought it might be water flow restriction-- although the circ. pump works fine as does the ozone unit.
When I turned the spa back on the green light would not light at all, and the no fault heater still would not work. I tested the power feed to the heater relay board and it was receiving electricity fine. Before I order a replacement heater, can anyone tell me if this symptom means something else is broken- like the heater relay board ..etc.? Something else I can test. I did test the heater with an ohm meter and it seemed ok, but I have little experience with this.