Lennox e-Lite LV-RC01 Installation And Operation Manual page 11

Installation
2) Lift up from the lower left end of the battery cover to open it (see
Figure 2.7);
3) Take out the old batteries. Install two new AAA batteries according to
the positive and negative polarities indicated (see Figure 2.8). Close the
battery cover.
Figure 2.6
Figure 2.7
Figure 2.8