How to Clean Commercial Hood Filters

Yes, stainless steel baffle filters can go through a high-temp commercial dishwasher, but do a preliminary soak first. If you skip the soak and throw heavily greased filters straight into the dish machine, you're going to clog your drain and your chef won't be happy about it. Get the bulk of the grease off with a soak, then let the dishwasher do the final pass. Aluminum filters are a hard no in the dishwasher. The alkaline commercial dish detergent eats aluminum. You'll pull them out looking chalky white and pitted. Not worth it. Just soak and scrub those by hand.

Here's what I tell every kitchen manager: if you hold a filter up to the light and can't see through it clearly, it should've been cleaned yesterday. Fryer-heavy kitchens with a lot of deep frying or charbroiling, that's a nightly job, no debate. Standard cooking, weekly is usually fine. But honestly the real answer depends on your volume. A slow Tuesday is different from a Friday dinner rush. Get in the habit of doing a quick visual check every night at close. Ten seconds to look at the filter can save you from a serious problem down the road.

Baffle filters are what you want in any serious commercial kitchen. The air hits angled metal vanes and has to change direction multiple times, and every time it does, grease sticks to the metal and runs down into the collection cup. They're fire-rated for a reason. Mesh filters work more like a screen, trapping particles, but once they're saturated there's basically no cleaning them effectively. I've tried. You end up just replacing them. And mesh filters aren't fire-rated, so they're not even legal in most commercial kitchens anyway. If you've got mesh, it's probably time to upgrade.

Don't do it. Bleach is an oxidizer, it's great for killing bacteria but it does nothing to break down grease. You'd basically be rinsing greasy filters with slightly blue water. Worse, if there's any ammonia-based cleaner nearby and you mix them, that creates chloramine gas, which is genuinely dangerous stuff. And bleach can corrode stainless steel over time with repeated exposure. Just get yourself a real alkaline degreaser, something specifically formulated for kitchen grease. Zep, Simple Green Heavy Duty, any restaurant supply brand. They're not expensive and they actually work. Bleach is for sanitizing surfaces, not degreasing equipment.

Baffles vertical, drain holes at the bottom. That's basically the whole thing. The reason orientation matters is physics: grease needs gravity to pull it down through those channels and into your collection cup. If you install them horizontally, grease pools inside the filter instead of draining, and it builds up fast. You'll also get reduced airflow because the baffles aren't cutting through the air correctly. Most filters have a label that says 'this side up' but after years of cleaning those labels fade. When in doubt, look at which way the grease channel runs and make sure it leads down toward the collection cup.

That means either you haven't been emptying it regularly or your filters are so clogged they're not draining properly anymore. The collection cup should be emptied every time you clean the filters, or more often if you're running heavy fryer volume. An overflowing grease cup is a fire hazard, full stop. The cup should unclip or slide out depending on your hood model. Empty it into a grease disposal container, not down the drain because that'll clog your pipes fast. Wipe the cup and track clean before putting it back. If the cup keeps filling up faster than expected, check your filter orientation first.