Recently I purchased a used 2000 Tiger River Bengal Spa, model M, it seemed to heat up fine yesterday, got it up to 98 degrees and took a soak.
This morning I went to get in and the temperature was only at 90 degrees. I’ve checked it through the day ( I do have a good cover on it) and it’s still at 90 degrees.
There are no bubbles coming up from the bottom vent I noticed. I removed the filter and still nothing. Jets work perfectly fine. Can someone please give me an idea on what could be wrong with it?