No, this toilet does not require an in-wall tank. It has a direct connection to the water supply.

An E4 error means either you need to change your air filters or your evaporator and condenser need cleansing. Another factor is there is no adequate power supply. However, it is best to contact our Customer Service Representative at support@troneplumbing.com.

It is recommended to clean the nozzle with a toothbrush coated with toothpaste. Please see page 25 of is instruction manual for more information.

No, the flush lever/multi function button is permanently mounted through the porcelain on the left hand side.

Yes you can adjust the seat opening distance. First, power off your toilet for at least 10 seconds. Then power back on your toilet and immediately after turning it on repeatedly press the "position" button on your remote control until you hear a double beep. Then press the right arrow repeatedly until you also hear a double beep. You can watch a video of this instruction here: https://youtube.com/shorts/FEuCgAF2OOQ. If you still need assitance, feel free to schedule a zoom call with our technicians who can work you through the settings or email support@troneplumbing.com

Thanks for your question!

To turn off/on Automatic Lid Opening/Closing press and hold the setttings button and then press the lid button.
To turn off/on Automatic Seat Opening/Closing press and hold the settings button and then press the seat button.

Please let us know if you have any additional questions. If you need additional support, you can always email support@troneplumbing.com.