1. Tub inline heater is designed to MAINTAIN the water temperature. It does NOT rapidly heat up the water.
2. 
   
3. Before you turn on the “Thermostat (inline-heater), you need to turn on the “Wave Massage (whirlpool-jet)” first.

1. When the inline-heater is on, you need to long-press the “Thermostat” button to get into the temperature adjustment mode.
2. The temperature screen will start blinking under the temperature adjustment mode.
3. Keep clicking on the “Thermostat” button until it reaches a desirable temperature.

Button on the tub top is to make a adjustment to the intensity to massage bubble's but only a small adjustment.  

Power Requirement

BM400 & BG400: 1 Dedicated 120V 30Amp Breakers

The bathtub can stay one color. By default, it will cycle through seven colors every time you turn on the machine. You can press the marked button to stay one certain color.