Wash cast grates on a legacy DCS cooktop or rangetop by hand with warm water and mild dish soap, dry them fully before they go back on, and keep them out of the dishwasher. Repeated dishwasher cycles are the most common thing that shortens the life of cast construction.
Why is the dishwasher hard on cast grates?
DCS built its indoor cooktops and rangetops with heavy cast grates designed for restaurant-style cooking, and with reasonable care they can outlast the kitchens they sit in. The most common thing that shortens their life is not heavy use but a cleaning routine that does not suit cast construction.
Running cast grates through a dishwasher repeatedly, even if they fit, exposes them to prolonged moisture and harsh detergent. That speeds up rust and can strip the seasoning or factory finish they have built up. A hand wash with warm water and mild soap, followed by thorough drying, holds up far better over the years.
The same logic applies to harsh oven cleaners. They are made for enamel and glass, and on bare cast metal they can strip protection faster than ordinary cooking ever would. Keep them off the grates entirely.
How do you spot a warped grate?
A grate with even a slight warp no longer sits flat. A pot on it then touches the support points unevenly, and that translates directly into uneven heating at the pot, separate from anything happening at the burner underneath.
Check a grate against a flat surface now and then, especially if cookware feels unstable or rocks slightly. Catching it early is easier than putting up with it.
Also look at how the grate sits on its supports each time you set it down. If one corner rocks, press gently on each corner to see which one lifts. That tells you where the warp is and whether it is getting worse.
Is discoloration a problem?
Usually not. A bronze or slightly rainbow tint from years of heat exposure is, in most cases, a cosmetic change and does not mean the grate needs replacing.
Pitting or flaking is different. Genuine surface loss, not just a color change, is the more meaningful sign of wear and is worth having assessed.
Should you season cast grates like cookware?
It is not strictly necessary, but it helps. After cleaning and drying, wipe the grate with a light coat of cooking oil while it is still slightly warm. Over time this builds a protective layer that resists rust and food sticking.
Owners who do it consistently tend to report that their grates hold up noticeably better than grates that only ever get a wash.
Use a neutral oil with a high smoke point and keep the coat thin. A thick layer turns sticky when heated and attracts more residue than it prevents.
What about storage and putting grates back?
If a cooktop or rangetop is removed during a kitchen remodel, store the grates somewhere dry. A garage or basement with humidity swings invites surface rust over months. A light coat of oil before storage, wiped off before reinstalling, lowers the risk further.
On some models, grates are sized to a specific burner position and are not fully interchangeable. If a grate seems to fit differently after a deep clean, make sure each one went back to its original position before assuming anything has warped.
When is replacement needed?
When a grate has warped or pitted enough to affect cooking, replacement parts for common CT, CS, CP and RGT grate sizes are generally available even though the line is no longer sold new. A technician can confirm the right size from your model number if you are unsure.
| Care task | How often | Why it matters | Notes |
|---|---|---|---|
| Hand wash with mild soap | After heavy spills or regularly | Avoids moisture and detergent damage | Dry completely before reinstalling |
| Light oil wipe | After cleaning and drying | Builds a rust-resistant layer | Apply while the grate is slightly warm |
| Flat-surface check | Every few months | Finds warping early | Check sooner if pots rock |
| Check burner positions | After each deep clean | Grates may be sized per position | Return each to its original spot |
| Dry storage during remodels | Whenever the unit is out | Prevents surface rust | Use a light oil coat, wipe before reinstalling |
Frequently asked questions
Can cast grates go in the dishwasher?
They may fit, but repeated cycles expose them to long moisture and harsh detergent, which speeds rust and strips seasoning or finish. Washing by hand with warm water and mild soap, then drying fully, is the safer routine.
Does a rainbow color on my grates mean they are damaged?
Usually no. Bronze or rainbow tones are typically a cosmetic result of years of heat. Pitting or flaking is the more meaningful sign of wear, and that is worth having a technician look at.
Are replacement grates still available for a discontinued DCS cooktop?
Generally yes. Parts for common CT, CS, CP and RGT grate sizes are available even though the line is no longer sold new. Confirm the model number first so the replacement matches your burner layout.