Lennox Merit MPE36 Service Manual page 14

If ember and flame lights
•Check the in-line fuse located to the
right of the control board.
•Perform a continuity test on the fuse. If
the multimeter displays "1" the fuse has
blown and must be replaced.
•If the bulbs and fuse test "OK" , check
the continuity of the control panel switch
(power On/Off) and (lights On/Off)
•If switches test OK then test control
board.
•L- Light to N-Light =114VAC
•L-Flame to N-Flame = 114VAC
fail to operate