How Often to Jet a Restaurant Grease Line

A grease line that backs up in the middle of service costs far more than the cleaning that would have prevented it. Lost covers, a closed kitchen, an emergency call at peak rates, and sometimes an unhappy health inspector all add up.

This guide explains how grease builds up in commercial kitchen lines, what decides how often they need jetting, and how to set a schedule that fits your kitchen rather than a generic rule.

How grease builds up

Fats, oils and grease, often called FOG, go down kitchen drains as liquid and cool as they travel through the pipe. As they cool they stick to the pipe walls. Food solids and soap residue catch on that layer, and the next batch of grease sticks to them.

The pipe narrows a little at a time. It drains normally until the day a busy service sends more water down than the narrowed line can carry. That's why grease backups often happen at the worst possible moment.

Where the trouble starts

• Lines from the dish area, where hot water and soap carry grease further before it cools.
• Floor drains near the fryers and cooking line.
• The line between the kitchen and the grease trap or interceptor.
• The line after the grease trap, if the trap isn't pumped often enough.
• Any low spot or bend where grease and solids collect.

Snaking vs jetting for grease lines

Snaking a grease line opens a path through the blockage, but most of the grease stays on the walls, so the line narrows again quickly. Hydro jetting scours the walls and removes the buildup, which keeps the line open longer between cleanings. For most commercial kitchens, jetting is the better maintenance tool. Our guide to hydro jetting vs snaking explains the difference in detail.

What sets your schedule

There's no single right interval. Two restaurants on the same block can need very different schedules. These are the factors that matter most.

Cooking volume and menu

A kitchen that fries all day produces far more grease than one that mostly bakes or grills. Busy kitchens fill lines faster.

Kitchen habits

Scraping plates into the trash, wiping pans before washing and keeping grease out of floor drains all slow buildup. Pouring grease down drains, even with hot water, speeds it up.

Grease trap maintenance

A grease trap or interceptor that's pumped on time catches grease before it reaches the sewer. A full trap lets grease through to the lines downstream.

The lines themselves

Older, smaller or sagging lines clog faster than large, straight, sound ones.

Setting a schedule that fits your kitchen

1. Start with a full jetting and a camera inspection after it, so you know the line is clean and in good condition.
2. Ask the plumber to record the footage and note any sags, bends or damage.
3. At the next visit, run the camera before jetting and see how much grease came back.
4. If the line was heavily coated, shorten the interval. If it was nearly clean, lengthen it.
5. Repeat until the interval catches buildup before it causes slow drains.

Keep the footage and notes from each visit. They show whether your schedule is working and help if you ever need to show your maintenance record.

Scheduling around service

• Book cleanings when the kitchen is closed, such as early morning or after close.
• Avoid the days right before your busiest periods, in case the work turns up a problem that needs a repair.
• Ask whether the plumber can work in the order that keeps the most drains usable, if you can't close completely.

Grease traps and grease lines are separate jobs

Pumping a grease trap empties the grease it has caught. Jetting cleans the lines that run to and from it. Many kitchens need both, each on its own schedule. A trap that's pumped on time protects the lines downstream; clean lines keep the trap from being overloaded.

SAWS has a fats, oils and grease ordinance for food businesses. Check its current requirements directly with SAWS, since rules and reporting can change.

Signs your schedule is too long

• Slow floor drains near the cooking line.
• Gurgling sinks during busy periods.
• Grease odors from drains.
• Backups during or right after peak service.
• Camera footage showing heavy grease at each visit.

If you're seeing these, ask for a camera inspection and shorten the interval. Call (866) 228-6201 to reach a licensed local plumber.

A kitchen routine that slows buildup

The cheapest way to stretch the time between cleanings is to keep grease out of the drains in the first place. A few habits make a real difference.

• Scrape plates and pans into the trash before they reach the dish area.
• Wipe greasy pans with a paper towel before washing.
• Collect used fryer oil in containers for recycling or disposal, never down a drain.
• Use strainers in sinks and floor drains, and empty them into the trash.
• Train new staff on these habits during their first week.
• Post simple reminders at sinks and the dish station.

What to keep in your maintenance file

• Dates of each line cleaning and grease trap pumping.
• The plumber's notes and camera footage from each visit.
• Any repairs, with the location and what was done.
• Any backups, with the date, time and which drains were affected.

A tidy record helps you adjust the schedule and gives you something to show if you're ever asked about grease management.

When a grease line needs more than jetting

Jetting removes grease. It can't fix a line that is cracked, sagging or too small for the kitchen's volume. If the camera shows a low spot that keeps filling with grease, or damage at the same place each visit, ask about repair options. A sagging section that's corrected can stretch the time between cleanings considerably.

Questions to ask a commercial plumber

• Can you clean the lines when we're closed?
• Will you run the camera after jetting and send us the footage?
• Based on what you see, how often should we schedule cleanings?
• Are there low spots or damage that make our lines clog faster?
• What should we change in the kitchen to reduce buildup?

Signs a backup is close

• Water pooling around floor drains during busy service.
• Sinks draining slowly after the dish station runs.
• Bubbling or gurgling in drains when other fixtures are used.
• A sour grease smell from drains, especially at the start of the day.

If you notice these, don't wait for the scheduled cleaning. Calling while the line is slow is cheaper and less disruptive than calling once it's backing up during service.

Working with your staff

The people at the dish station and on the cooking line decide how much grease reaches the drains. Explain why the routine matters, not just what to do, and make the right choice easy: put trash cans and grease containers where people need them. When a backup happens, share what the plumber found so the team can see the connection between habits and clogs.

Restaurants, cafeterias and other kitchens

The same principles apply to any commercial kitchen: restaurants, food trucks with fixed connections, school and hospital cafeterias, hotel kitchens and catering operations. What changes is volume. A cafeteria that cooks once a day at large scale may need a different schedule from a small restaurant that fries all day. Let the camera footage, not the type of business, set the interval.

After a backup during service

1. Stop sending water to the affected drains and, if needed, pause the dish station.
2. Call for an emergency cleaning and ask for a camera inspection once the line is clear.
3. Note the time, which drains backed up and what was being cooked.
4. Ask the plumber where the buildup was heaviest and whether the schedule should change.
5. Review kitchen habits with staff, using what the plumber found.

A sample routine for the first year

Every kitchen is different, but a first year often follows a pattern like this. Start with a full jetting and camera inspection to set a clean baseline. Book the next cleaning at an interval the plumber suggests from what they saw, and run the camera before jetting at that visit. If the line was heavily coated, bring the next one forward; if it was nearly clean, push it back. By the end of the year you'll have several visits of footage and a schedule based on your own kitchen rather than a guess.

Common questions