Leviticus 6:9

6:9 “Command Aaron and his sons, ‘This is the law of the burnt offering. The burnt offering is to remain on the hearth on the altar all night until morning, and the fire of the altar must be kept burning on it.

Leviticus 6:12

6:12 but the fire which is on the altar must be kept burning on it. It must not be extinguished. So the priest must kindle wood on it morning by morning, and he must arrange the burnt offering on it and offer the fat of the peace offering up in smoke on it.