I have a 2004 Tiger River bengal spa. A few weeks back I noticed the temperature in the tub had cooled down. At first I thought the circ. pump was out as I could not detect much flow from the outlet in the bottom of the tub. I pulled the panel off and the pump was running. I attached a piece of tubing to the ozonator connection on the discharge side of the pump and raised the tubing above the water level. I powered the tub up and had flow coming out of the tube. I also put a piece of plastic over the outlet in the tub and noticed I had flow there since the plastic would not stay over it. I put everything back as it was and pushed the reset on the heater just for the hell of it. The tub heated back up to 102 degrees and all was good. A week passed and I went on a 3 day trip. When I came back the water felt cool so I put a thermometer in it and it read 94 degrees with the tub set at 102 degrees. It has maintained 94 degrees now for two days but will not heat further. The only work I have done on the tub was I replaced a burnt heater board two years back. I live too far in the boonies for repair service at a resonable cost. Any ideas on whats going on? Thanks for the help.