Just wanted to offer up some advice and also find out if anyone else has had this problem. We just finished a kitchen remodel. We baked and broiled this weekend with our new slide-in range for the second time. The grout behind the 2 center heat outflows is burnt (not stained) but burnt. The porcelain tiles are slightly discolored too and I have tried everything to clean them. The service guy was out this morning and couldn't find anything wrong with the range. I asked the contractor to use Laticrete Spectralock for easier cleaning. My bad for not checking heat tolerance first. It only tolerates heat up to intermittent 250 F or constant 150 F. Just wanted to offer that info if it might help someone out there. Does anyone know of a high-heat tolerant grout? Thanks so much!