Installed a Raypak 8450 heat pump in October 22, has worked fine maintaining my 12000 gallon above ground swimming pool at 83 degrees with no issues. It's when i use the spa that I have a problem. I have spa set at 98 degrees, heat pump heats it fine until it gets to around 92 degrees, then heat pump trips off due to high pressure, today was only the second time i have used the heat pump for the spa, it had a problem the first time i used it, but only shut down a couple of times and then made it to the set temperature. Today, I couldn't get the spa above 95 because it kept shutting down. The heat pump was professionally installed and is under warranty. I have a pentair VS pump 3.5 hp and 2" plumbing. there is a bypass valve installed. I have changed the pump speed from 1500 rpm to 3200 rpm, as well as adjusting the bypass, problem still occurs. All filters and baskets are clean. After putting equipment back to pool mode, the heater again worked fine, pool temp was 80 degrees. Heat pump ran fine like it always does in pool mode. I am thinking it has something to do with the temperature of the spa water and the refrigerant pressures. Any ideas of what could be going on is appreciated. If necessary, I can place a service call. Thanks