Spa was running great...then no heat. "expert 1"...replace the heater element...done, along with the pressue switch and high limit switch; no heat...expert 2...must be the control module, done, replaced the whole unit along with the sensor bulb. Then it was the relay switch...replaced. Now the tub heats to 90 degrees, but the ciruclation pump doesn't shut off...will not heat to full temp...relay 'rattles', ready light is on. Could the heater be miswired? Suggestions? Dumped $500 in it all ready with parts and service calls. ANy idea where I could get a wiring diagram...I'll do it myself. Thank you for any suggestions or help!!