Lately I've been leaving my easytouch system set to 'Solar Preferred' heating because it usually doesn't get warm enough to trigger solar until mid-day and we like to take our 1 and 2 year old swimming some days before their afternoon naps. Solar Preffered mode uses the gas heater if the solar temp isn't high enough for solar mode. This usually works well as over-night the pool usually dips into the mid 70's (we don't use a blanket) and a couple of hours of gas heat in the morning get it into the 80's and then the solar finishes bringing it up to the 85 degree set point and maintains it for the day.
Yesterday morning before I left for work I changed it from 'solar only' to 'solar preferred' since my wife was going to have some friends over and they thought they might go swimming. The temp was the usual mid 70's. They ended up not going swimming and that night after dinner I just happened to dip my toes in the pool and noticed it was HOT. I grabbed the thermometer and sure enough, the water was 98 degrees in the pool!
The only way that I can see this occurring is that the easytouch relay which powers the heater must have gotten stuck. The pool temperature set point was 85 and even if somehow it had gotten into Spa mode yet neglected to move the valves, the spa set point was only 95. A temp of 98 in the pool (and this is an hour or so after the pumps shut off at 5:00) can only mean that the heater ran all day long and then shut off when the pool pump shut off.
Has this happened to anybody else? My equipment is less than a year old so I suppose I need to have the PB come out and swap some relays but I definitely want to make sure it doesn't happen again.