The vat heater has to be installed inside the vat on the bottom. You will have 2 clamps that screw into the vat to keep the heater in position. The cable of the heater should sit on the left side of the vat.
Please do note the heater uses high voltage at the moment. Please do not connect/disconnect the heater while the power cable is connected to the printer.
The orange cable shows where the heater cable routes through on the back left side. Some of our clients have said it seems that it is better to take the cable through the front of the vat because there is more space between the build plate and the bend.