Turn other residential burners down to simmer and the flame looks much the same as before, only smaller. Not so at DCS. The primary flame on our sealed Dual Flow Burners™ shuts off automatically when you turn it to simmer, leaving a smaller “retention flame” burning. This allows you to maintain a constant simmer temperature as low as 140 degrees, for an efficient and safe simmer. This means no more scalding delicate sauces.