What Is a Range Hood Grease Trap? (Clean Specs)
A range hood grease trap is the removable cup or trough beneath a hood’s grease filter. It catches grease that drains from the filter; it does not replace the filter or clean the exhaust duct. Use only the cup and filter specified for the hood, fit them as directed, and empty the cup before it overflows.
A quick way to avoid a wrong replacement is to find the hood’s model number before measuring or ordering parts. A cup can look close to the original yet fail to seat or drain as intended. I treat the hood, filter, and cup as one matched system, not as interchangeable metal parts.
Identify the Grease Cup, Filter, and Hood Specifications
A hood grease cup collects liquid grease that runs off the filter during cooking. The filter captures grease-laden vapor as air passes through it. Together, these parts help manage grease in the ventilation system, but they do not eliminate the need to clean the duct or other hood components.
The word “trap” can cause confusion. A hood grease cup is not a plumbing grease interceptor, which is a separate device used in some drainage systems. The hood cup is usually a removable component mounted beneath the filter or along a hood’s lower edge. Its shape and mounting method depend on the hood design.
Find the correct part
Start with the hood’s nameplate, manual, or manufacturer parts list. Record the model number and check whether the parts list names a grease cup, trough, filter, or a complete filter assembly. If the hood has more than one filter, confirm how many cups it uses and where each one belongs.
A replacement should match the specified part and fit the hood without force. Check its dimensions, mounting points, drain features, and required orientation against the manufacturer’s instructions. A similar-looking part is not a safe substitute if it will not sit securely or could block airflow.
| Item to verify | What to check | Why it matters |
|---|---|---|
| Hood model | Model number on the hood or in its manual | Parts are model-specific |
| Filter | Manufacturer-approved type and orientation | The filter is part of the listed hood system |
| Grease cup | Correct part number, shape, and mounting | A poor fit can spill or fail to collect runoff |
| Material | Manufacturer’s stated material and cleaning advice | Cleaner compatibility varies |
| Exhaust setup | Hood and filter instructions for the installed system | The cup does not establish system compatibility |
| Safety marking | Filter listing or marking, where applicable | UL 1046 is a relevant grease-filter safety standard |
UL 1046 covers grease filters. Check the filter’s marking and the hood documentation for its listed use and approved installation orientation. Do not assume that a filter is acceptable because it fits physically. For commercial cooking ventilation, NFPA 96 may also apply; follow the locally adopted edition and the authority having jurisdiction (AHJ), the local agency responsible for enforcement.
What material and “capacity” tell you
Stainless steel is generally corrosion-resistant. Aluminum is lighter, but it can be more vulnerable to alkaline cleaners. These are broad material traits, not permission to use any cleaner or to swap parts. Follow the hood maker’s guidance for the specific cup and filter.
There is no universal cup capacity, operating-temperature limit, or cleaning interval. Hood designs, cup dimensions, drainage arrangements, cooking volume, and instructions differ. Do not infer a temperature rating from the metal type. Use the limits stated by the hood, filter, and cup manufacturers.
These parts are not cookware. Induction compatibility, oven ratings, and cookware heat-diffusion claims do not apply to a hood grease cup. The practical questions are whether the part is specified for the hood, fits securely, drains or collects as designed, and can be cleaned as directed.
Install and Operate the Grease Collection System
Correct installation keeps the filter and cup in their intended positions while the hood moves air. Before work, switch off cooking equipment and let the hood components cool. Follow the manual’s removal and installation steps; do not bend, modify, or force a part to make it fit.
Installation and start-up checks
- Confirm the parts. Match the filter and cup to the hood’s model and parts list. Check the filter’s specified orientation.
- Inspect before fitting. Look for dents, corrosion, damaged seams, blocked drains, or missing clips and supports. Do not install a damaged cup or filter.
- Seat the filter. Install it in the direction and position shown by the manufacturer. A filter that is reversed or loose may not function as designed.
- Fit the cup. Slide or secure it into the intended mounts. Confirm that it is level if the design requires that, and that it cannot shift during normal operation.
- Check the area. Make sure the cup does not interfere with the filter, controls, lights, or other hood parts.
- Operate and monitor. Run the hood at the required setting while cooking. Check the cup routinely and empty it before grease nears the rim.
Do not run the hood with a missing, overflowing, or misseated cup if the manufacturer requires one. Grease may spill onto the hood or cooking surface, raising fire and contamination risks. Stop cooking and correct the fault before using the system again.
A cup is only one part of grease management. It does not replace cleaning the filter, hood interior, ducts, or exhaust fan. Those tasks follow the appliance instructions and, in commercial kitchens, the applicable fire code and inspection requirements.
Practical fit checks
A correctly installed cup should stay in its mounts and catch runoff where the hood maker intended. If it rocks, slips, leaves an obvious gap, or drains toward the cooking area, stop and recheck the part number and orientation. Do not use tape, wire, or a homemade bracket as a substitute for the specified attachment.
If a cup has a drain opening or plug, verify the manufacturer’s intended arrangement. Do not assume that a drain should connect to plumbing or that it can remain open. The installation must match the product instructions and applicable local requirements.
Empty, Clean, Inspect, and Reinstall Components
Routine care removes collected grease before it spills and helps reveal damage early. Let the hood and parts cool before handling them. Wear gloves, remove the cup and filter as directed, and use cleaning products approved for those materials.
Safe cleaning sequence
- Switch off and cool. Turn off cooking equipment and allow the hood parts to cool. Never pour hot water or cleaner onto hot components.
- Remove carefully. Use the manual’s method and support the cup as it comes free so collected grease does not spill.
- Empty into a suitable waste container. Dispose of grease according to local rules. Never pour it into a sink, floor drain, or other plumbing drain.
- Wash with a compatible detergent. Follow the maker’s cleaner guidance. Avoid caustic or abrasive products unless the manufacturer specifically permits them.
- Rinse and dry fully. Check seams and corners for residue, then dry the parts before reinstalling them.
- Inspect and refit. Look for corrosion, distortion, cracks, blocked passages, and loose mounts. Reinstall only serviceable parts, fully seated and correctly oriented.
Do not clean a cup while it is hot, and do not use a harsh cleaner just because the part is metal. Material and finish can affect cleaner compatibility. If the manual does not identify an approved cleaner, contact the manufacturer rather than testing an aggressive product.
A cup that is dented enough to sit poorly, has a failed seam, or cannot be cleaned should be replaced with the specified part. If grease has spilled inside the hood or onto nearby surfaces, clean the affected area safely and check for further buildup before resuming use.
Maintain a Safe, Clean Cooking and Dining Area
Keeping the cup below its overflow point is a simple daily control, but it does not prove that the full exhaust system is clean. Inspection and cleaning needs depend on the kind of cooking, the amount of use, and the rules that apply to the building.
For commercial systems, NFPA 96 gives inspection baselines that depend on cooking type and volume. The commonly cited intervals are monthly for solid-fuel cooking, quarterly for high-volume cooking, semiannually for moderate-volume cooking, and annually for low-volume cooking. Confirm the locally adopted edition and AHJ requirements, and clean sooner whenever grease buildup warrants it.
| Commercial cooking condition | NFPA 96 inspection baseline |
|---|---|
| Solid-fuel cooking | Monthly |
| High-volume cooking | Quarterly |
| Moderate-volume cooking | Semiannually |
| Low-volume cooking | Annually |
These are inspection baselines for commercial exhaust systems, not a universal schedule for emptying a grease cup. Cup checks may need to happen much more often, based on cooking volume and what you observe. Residential users should follow the hood manual and local requirements rather than applying commercial intervals automatically.
Field scenarios: what to do
These examples are practical situations, not reports of measured installations. They show how to apply the checks without guessing at a capacity or code rule.
- A residential cup fills quickly during frequent frying. Check it during cooking and empty it before grease nears the rim. Confirm that the correct filter is installed and clean it as directed. If buildup persists, consult the hood manual or service provider; do not fit a larger improvised cup.
- A replacement cup sits loosely. Stop using the hood until you confirm the part number, orientation, and mounting method. A loose cup may spill or fail to collect grease. Do not secure it with an improvised fastener.
- A commercial kitchen has visible grease in the hood or duct area. Do not treat an empty cup as evidence that the exhaust system is clean. Arrange inspection or cleaning based on cooking type, applicable NFPA 96 provisions, and AHJ rules.
- A cup or filter is missing. Do not operate the system if the manufacturer requires that component. Replace it with the specified part and verify secure installation before cooking.
Frequently Asked Questions
These answers clarify the part’s purpose, fit, care, and limits. The hood manual and local rules control where they give specific requirements. If a part is damaged or its installation is unclear, verify the model and consult the manufacturer or a qualified service provider.
Is a range hood grease trap the same as a grease interceptor?
No. A hood grease cup catches grease runoff beneath the filter. A plumbing grease interceptor is a separate device in a drainage system. Do not connect a hood cup to plumbing unless the manufacturer and applicable requirements specifically call for that arrangement.
Does the grease cup filter grease out of the air?
No. The hood’s filter captures grease-laden vapor as air passes through it. The cup collects grease that drains from the filter. Neither part replaces cleaning the hood and exhaust system.
How often should I empty the grease cup?
There is no universal interval. Check it routinely and empty it before grease nears the rim. How often it fills depends on the hood design and cooking volume.
Can I use a universal grease cup?
Only if the hood manufacturer identifies it as suitable for your model. A cup that looks similar may not fit, orient, or collect grease correctly.
Can I use any metal filter that fits?
No. Use the filter specified for the hood, in its approved orientation. UL 1046 is a relevant grease-filter safety standard; check the filter marking and hood documentation.
What cleaner should I use?
Use a detergent approved for the cup and filter materials. Stainless steel and aluminum can respond differently to cleaners, so follow the manufacturer’s instructions and avoid unapproved caustic or abrasive products.
Can collected grease go down the drain?
No. Put it in an approved waste container and dispose of it under local rules. Do not pour it into a sink or other drain.
What if the cup overflows or is missing?
Stop cooking and correct the problem before operating the hood again. Grease can spill onto the hood or cooking surface, creating contamination and fire risks.
Does an empty cup mean the duct is clean?
No. The cup only collects runoff from the filter. Inspect and clean the filter, hood, duct, and exhaust fan as required by the manufacturer and applicable commercial rules.
Are NFPA 96 inspection intervals required in every home?
No. NFPA 96 concerns commercial cooking ventilation and fire protection. Requirements depend on local adoption and the AHJ. Residential hood owners should follow the hood instructions and local rules.
(This article was written by one of our staff writers, Julian R. Hayes. Visit our Meet the Team page.)
