FD4-125

Overview

The Hobart FD4-125 is a commercial food waste disposer in Hobart’s FD4 series. It grinds food waste to small particles for discharge through the waste line. The grinding action comes from hardened stainless steel cutter blocks mounted on a rotating flywheel working against a stationary shredder ring; flushing water helps carry the ground waste away. The disposer is self-feeding, so operators do not need to push waste into the grinding mechanism. The manual states that it can be filled with waste while idle and will start and operate at full load.

This model is intended for commercial use only. Hobart describes the FD4 range as suitable for small- to medium-sized cleanup systems, with control and accessory groups available for different installations. The basic unit is supplied without an accessory group or controls.

Key Features

• Commercial motor: The FD4-125 has a 1-1/4 HP motor with continuous-duty rating and a manual-reset, inherent thermal overload protector.
• Grinding components: Two hardened stainless steel cutter blocks are fastened to the flywheel. The blocks can be replaced and indexed to present new cutting edges.
• Dual-direction grinding: The disposer can grind in either direction of flywheel rotation. Automatic reversing is available when installed with Control Group 5 or 6; Hobart notes this disperses wear and can help free a jam.
• Serviceable construction: Heavy aluminum grind and discharge housings are joined to the motor unit with four bolts, permitting removal of the motor unit from the grind chamber.
• Vibration isolation: A vinyl isolating ring at the cone mount prevents metal-to-metal contact and reduces transmission of vibration and noise.
• Water flow: A 5-gallon-per-minute flow control is specified for FD4-series models FD4/50 through FD4/125.

Specifications

• Model: Hobart FD4-125 (also identified in Hobart documentation as FD4/125).
• Equipment type: Commercial food waste disposer.
• Motor output: 1-1/4 HP.
• Motor duty and protection: Continuous duty; manual-reset inherent thermal overload protector.
• 60 Hz, single-phase electrical options: 120/208-240 V; rated amps 11.1/5.05.
• 60 Hz, three-phase electrical options: 208-240/480 V; rated amps 4.0/2.0.
• 50 Hz, single-phase electrical options: 110-120/220-240 V; rated amps 12.8/6.4.
• 50 Hz, three-phase electrical options: 220-240/380-415 V; rated amps 4.6/2.3. The Hobart sheet notes that 50 Hz electrical specifications were not submitted for UL listing.
• Grind and discharge housings: Heavy aluminum.
• Flywheel: Ni-Resist, 6 3/16-inch diameter, with a centre breaker blade.
• Cutter blocks: Two hardened stainless steel blocks, replaceable and indexable.
• Stationary shredder ring: 1 3/4 inches high, with 4 machine-ground primary-action breaker bars and 42 secondary-action grinding teeth.
• Motor shaft seal: Cartridge-style mechanical face seal.
• Waste connection: Chrome-plated brass tailpiece for a 1 1/2-inch standard drain trap. The installation manual describes a 1-1/2-inch O.D. waste discharge spout.
• Water flow control: 5 gallons per minute, 3/4-inch N.P.T.
• Mounting: Hobart disposers normally mount to cones with a 7-inch I.D. throat opening; accessory Group E is the stated exception.
• Shipping weight: Approximately 60 lb, excluding accessories and controls.
• Standard: Hobart’s FD4 specification sheet states compliance with ASSE 1009.

Installation & Requirements

Installation must follow applicable sanitary, safety, plumbing and electrical codes. Before installation, check that the electrical service matches the disposer data plate. Provide temporary support while positioning the disposer. The manual specifies a dedicated motor-control switch with a marked OFF position that disconnects all ungrounded supply conductors; it must be within sight of the disposer or sink opening. Disconnect power and follow lockout/tagout procedures before making electrical connections. Use the wiring diagram supplied with the machine for the disposer and electrical service. Flexible conduit is specified to allow the unit to be moved for periodic service and maintenance.

For standard cone mounting, the disposer attaches to a cone with a 7-inch I.D. throat opening. The vinyl isolating ring fits at the cone mount. The manual also describes an accessory Group E sink adapter for 3-1/2- to 4-inch sink openings, used with the short upper housing; this is an accessory arrangement, not a different description of the FD4-125 itself.

For the waste connection, the manual specifies a 1-1/2-inch O.D. discharge spout suitable for a standard trap. Keep the waste line run as short as possible with the best fall available. The waste exit must not be higher than the centre line of the disposer waste outlet. Clean existing waste lines thoroughly, remove burrs from cut pipe ends and use fittings that allow unrestricted flow. Do not use drum traps or grease traps.

Connect the disposer swirl to a 3/4-inch IPS cold-water supply and install the supplied 5-gallon-per-minute flow control. The disposer requires a minimum flow pressure of 16 psig. If water pressure exceeds 60 psig, the manual calls for a pressure-reducing valve. Install a shut-off valve for servicing. Control groups are supplied with a solenoid valve, which must be fitted in the water supply line as shown in the manual. Install a vacuum breaker in accordance with local plumbing codes; where local codes prohibit a vacuum breaker, the manual specifies an air-gap water inlet instead.

Operation

Before starting, check that the disposer is clear of foreign objects that may have entered during installation and check flywheel rotation. Never use a hand to check rotation or remove foreign matter. Use a stick or similar object to turn the flywheel; remove foreign objects with tongs or pliers. Start the disposer before feeding food waste and make sure water is flowing. With typical optional controls, starting the disposer and turning on the water happen simultaneously and automatically.

Feed food waste into the disposer without forcing it into the grinding mechanism. Do not put china, metal, rags, clam shells or similar material into the unit. Do not put grease or oil into the disposer, as it can clog the drain. Let the disposer run briefly after grinding is complete so the unit and waste line flush properly; certain optional controls provide this flushing automatically. Never reach inside while the disposer is operating.

The manual prohibits drain cleaner, glass, china or plastic, large whole bones, metal items such as bottle caps, tin cans or aluminum foil, and whole cornhusks. Keep the vinyl silver-trap scraping ring or sink stopper in place, even when the disposer is not in use, to reduce the chance of objects falling into it.

Cleaning & Maintenance

After disposing of food waste, allow the disposer to run for a few minutes to flush the interior. If waste is left to accumulate, it can cause offensive odours. For heavier cleaning, the manual describes using a stiff brush with a strong soap-and-hot-water solution. For light cleaning, grind ice and a lemon through the disposer.

Only damp-wipe the exterior of the disposer and its controls. Do not hose down their exterior surfaces. The manual identifies removable hardened-steel grinding components and replaceable cutter blocks; cutter blocks can be indexed for new cutting edges. The motor has permanently lubricated ball bearings, and its upper bearing is sealed on both sides.

Troubleshooting

The motor includes a manual-reset inherent overload protector. The provided manual excerpt does not give a reset procedure, so follow the instructions for the installed controls and service documentation rather than reaching into the disposer. If a jam occurs, set the power switch to OFF before clearing it or removing an object. For disposers wired to Control Group 4 or a Group 5 centre, the manual directs operators to shut off the branch-circuit main switch or disconnect; with a Group 6 control panel, turn off the emergency disconnect. Use long-handled tongs or pliers to remove objects. Control Groups 5 and 6 provide automatic reversing, which can help free a jam.

Do not install or operate a disposer that has been dropped or damaged. The manual directs the user to contact a service centre for examination, repair or adjustment. It also advises checking for shipping damage after unpacking and contacting the carrier within 15 days if damage is found.

Applications

The selector chart is based on an average food-waste mix and uses 1/2 lb of food waste per person per meal as a guide. If waste contains a large percentage of bones or other hard material, Hobart recommends specifying a larger disposer or additional units. The manual states that the FD4-125 is for commercial use only and is not intended for residential applications.