Automatic Electrical/Mechanical GRUs remove surface grease daily and GRUs operate on a timer. When activated the GRU typically heats up the grease allowing it to be easily collected using some sort of skimming device which directs the grease into a receptacle for easy disposal into the trash, or a grease reclamation bin. A basket installed on the inlet to the GRU screens out solids and must be emptied daily.
These units are small which allows for installation inside the kitchen, typically under the three-bay sink. They are sized based upon sink size and other equipment connected to the GRU.
All wastewater from food preparation and/or washing and clean‐up operations, including but not limited to pot sinks, pre‐rinse stations, wok stations, soup kettles, braising pans, mop sinks and wastewater generated from exhaust fan hood cleaning operations must discharge to the grease removal device. All automatic dishwasher wastewater, excluding pre‐rinse stations must bypass the grease removal device and be discharged directly into the sewer system downstream of the GRU.
No wastewater, other than from kitchen fixtures or food processing equipment, shall discharge into the GRU unless approved by the NBC in writing. Wastewater from sanitary sources such as toilets and bathroom sinks is prohibited from being discharged to the GRU. Garbage disposal units are prohibited in facilities which utilize Automatic Electrical/Mechanical GRUs.
Automatic GRU Maintenance
Automatic GRUs require daily maintenance. These units must be inspected every workday to determine whether the system is functioning normally or in need of cleaning, grease disposal or any corrective measures. Maintenance activities include, but are not limited to the following:
- The solids basket or strainer must be cleaned and emptied into the trash.
- The wiper blades and the trough must be cleaned of accumulated grease.
- The GRU should be wet vacuumed or completely cleaned out as needed.
Wastewater Discharge Permits require maintenance activities to be documented in a logbook. The logbook must be kept near the GRU at all times and must be available to NBC personnel for their review.