This is the 4KW PDR heater, built without a pressure switch. Please note that if your spa was designed to use the heater with a pressure switch, you can still use this heater, but you will also have to apply a jumper on connector P34 on the IQ2020 main board.
This heater is designed for the following models:
| Model | Start SER# | End SER# |
| SS, KK | 1F1001 | current |
| GG | 3G1001 | current |
