to stew, simmer, banked fire
煨 centers on cooking with gentle, indirect heat: stewing, simmering, or using a banked fire to maintain low, steady warmth.
煨 combines 火 (fire) with 畏, which likely contributes the sound and suggests a subdued or contained quality, fitting the idea of a low, banked fire for slow cooking.
The left side is fire 火, and the right side 畏 looks like a pot with a lid over a field 田 and cloth 衣, as if covering the fire to keep it low. Picture a pot simmering gently on a banked fire, the heat just enough to stew the contents.
For ワイ, imagine asking 'Why?' (ワイ) the fire is so low—because you're simmering a stew, not boiling it. The 'why' sound hooks the reading while the low fire fits the meaning.