Models part 9006666015 fits
If the pilot won't stay lit, this is the usual suspect. Find your model number below before you order; the list is sorted by brand.
GCV40-200AO Smith water heaterGCV50-200AO Smith water heaterGVR40-200AO Smith water heaterGVR50-200AO Smith water heaterXCV50-200AO Smith water heaterXCVL40-200AO Smith water heaterXVR50-200AO Smith water heaterGS640YOCS200State water heaterGS640YOCT200State water heaterEach model's page names where its part numbers come from and the date they were checked. Amazon buttons open a search for the part number; we may earn a commission.