This hot tub sat for about a year, When I first plugged it in it worked and heated up well. The pump is two speed and now only turns on when the jets are activated and it won't heat or circulate on low speed. I had a spa place quote me $409 for a new heater and they believe that's the issue. Does anyone know of any cheaper alternatives? I can do the work myself I'm just not sure what heater I should be looking for. Thanks!