charger_1 wrote:
you didn't mention wether your spa is 120 or 240V, wether or not it has a cover, etc... all will dictate how long it takes to heat. Most spas don't heat when jets are on. It is a power issue. Takes a huge amount of amperage to run everything at once. Timer is more of a money-saver in terms of efficiency than anything. If it were me, I'd leave it as is.
240V with insulated cover. Outside temperature usually 100+. The heating timeframe has definitely increased. Do you suppose this would be the element or thermostat?