Garbage Disposal Installation & Replacement
Fitting a disposal properly is a good deal more than bolting a unit under the sink. We size it to the household, bed and set the mount, connect the trap and the dishwasher correctly, and sort out the switching. Licensed California contractor #1082507, serving Union City and 15 Bay Area cities. Your quote is approved before any work starts.
If your existing unit hums, jams or leaks and you would rather repair than replace, see our garbage disposal repair and jam clearing service.
- New disposal fitted where there was none
- Like-for-like replacement of a failed unit
- Sizing by motor power and household use
- Sink flange, mount and trap connections
- Dishwasher drain hookup and knockout plug
- Wall switch or counter-top air switch
- Old unit removed and taken away
Signs You Need Garbage Disposal Installation
Catching these early is almost always cheaper than waiting for the failure.
The unit hums but will not turn
A motor that hums without rotating usually means a jammed or seized rotor. A jam can be freed with the hex key. A seized motor, or one that trips its reset button every time it is used, has reached the end of its life. We tell you which of the two you have before suggesting a replacement.
Water dripping from the body
Leaks at the sink flange or the drain elbow are straightforward repairs. A leak coming from the seam of the housing itself means the internal seal has failed and water is getting past the motor. That unit is finished, and replacing it is the only sensible answer.
Slow, noisy and getting worse
Grinding, rattling or a unit that takes far longer than it used to points at worn impellers and a corroded grind chamber. Bay Area hard water speeds that along. Once the chamber is pitted, food packs rather than clears and the drain below starts blocking more often.
No disposal fitted at all
Plenty of older East Bay kitchens never had one. Adding a disposal means a new sink flange, a trap arm at the right height, switching, and in some cases a dedicated outlet under the cabinet. We handle the plumbing side and tell you plainly what the electrics need.
A new sink or worktop is going in
A new sink usually means a new flange, and often a different bowl depth, which changes the trap geometry underneath. If the disposal is already several years old, refitting it under a brand new sink is a false economy. This is the natural moment to replace it.
The dishwasher backs up into the sink
Dirty water standing in the bowl after a dishwasher cycle almost always points at the disposal connection. The usual culprits are the knockout plug left in place on a new installation, a drain hose with no high loop or air gap, or a clogged inlet spigot.
Choosing the Right Unit
Continuous feed
The common type. Switch on, feed waste in with cold water running, switch off. Simpler, cheaper and quicker to fit, but it needs a wall switch or an air switch at the sink. It suits most households. The trade-off is that the opening is live while it runs, so the splash guard needs to be in good condition.
Batch feed
You load the chamber, fit the stopper and twist to start, so it cannot run with the opening open. That is why people choose it in a house with young children. Units cost more and hold less per batch, but no wall switch or switch wiring is needed if there is already a receptacle under the sink.
Motor size and grind stages
Light use in a small household is fine on a smaller motor. A busy kitchen, a lot of vegetable prep or a long horizontal drain run wants more power and multi-stage grinding, which reduces particle size and the chance of a block further along. We size it to how you actually cook, not to what the box says.
Sound insulation and septic systems
Insulated models are noticeably quieter under a stainless sink, which is worth having in an open-plan kitchen. If the property is on a septic system rather than sewer, say so when we quote. What goes into a disposal matters a great deal more there, and both the unit and the habits need to suit the tank.
How We Fit a Disposal
Look at what is under the sink
Before anything is ordered we check the cabinet: existing power and switching, trap height, the dishwasher hose route, and whether the flange will suit the new unit. On a photo or video quote, that is exactly what we ask you to show us.
Agree the unit and the price
We recommend a size and type for your kitchen and give you a written price covering the unit, the fitting and removal of the old one. Most quotes are free. Nothing is ordered and nothing is taken out until you approve it.
Remove and prepare
The old unit comes out, the sink flange is cleaned back to bare metal and re-bedded with fresh plumber's putty, and the mounting ring is set square and pulled down evenly. A flange bedded on old, hardened putty is the single most common source of a slow cabinet leak.
Connect drain, dishwasher and power
The unit hangs on the mount, the discharge tube meets the trap arm with proper fall on it, and the dishwasher hose connects to the inlet with the knockout plug driven out and removed. Power goes to a wall switch or a counter-top air switch.
Test and clean up
We fill and drain the bowl, run the dishwasher through a drain cycle, check every joint dry with a torch and paper, then run the disposal under load. The old unit and the packaging leave with us, and the cabinet goes back as we found it.
Getting a Disposal Installation Right
Most disposal problems that surface a year after fitting come from the connections rather than the appliance. The sink flange has to be bedded properly and pulled down evenly or it will weep quietly into the cabinet, where nobody notices until the base swells. The discharge tube has to meet the trap arm with fall on it, not sit level or run slightly uphill, because a horizontal section with no fall is where ground food settles and builds into a block.
The dishwasher connection catches people out constantly. A new disposal ships with a solid knockout plug closing the dishwasher inlet. If that plug is not driven out and removed before the hose goes on, the dishwasher has nowhere to drain and backs up into the sink. The plug also has to be fished out of the chamber afterwards, or it rattles around and jams the impellers. It takes two minutes and it ruins an installation when it is skipped.
Motor size matters less than the marketing suggests, but it is not nothing. What actually decides it is how you cook and what the drain looks like downstream. A small flat with a short drop to the stack is fine on a modest motor. A busy family kitchen at the end of a long horizontal run through an older home benefits from more power and finer grinding, because anything leaving the chamber in large pieces has a long way to travel before it gets anywhere useful.
Older East Bay kitchens frequently have no dedicated power under the sink and nowhere sensible for a switch, so adding a disposal where there was none is partly an electrical question. We will tell you honestly what the cabinet needs. A counter-top air switch is often the neatest answer in a kitchen with no convenient wall position, because it operates the unit pneumatically and puts the button where your hand already is.
What Affects the Price
We quote every job up front, so you approve the price before anything starts. These are the things that move it:
- The unit itself, including motor size, grind stages and sound insulation
- Replacement versus a first-time installation with no existing mount
- Whether power and switching already exist under the sink
- Fitting a counter-top air switch, including drilling the worktop
- Condition of the sink flange, trap arm and existing drain
- Adding or correcting a dishwasher air gap where code requires one
- Removal and disposal of the old unit
Most quotes are free and can be done from photos or video you send us. Some on-site estimates carry a fee based on distance, and we tell you that before we come out.
Making a New Disposal Last
Cold water before, during, and for a good twenty seconds after. It keeps fats solid so they get ground and carried out of the house, rather than melting and coating the inside of the pipe further down the run.
Fibrous strings, onion skins, coffee grounds, eggshells, rice, pasta and bones cause most jams and blocks. Fat and grease belong in the bin, not the sink, whatever the unit is rated to handle.
Small amounts with the water already running beats stuffing the chamber full and then switching on. Overloading is what trips the reset button and what wears impellers out years earlier than they should.
A disposal left unused for weeks corrodes and seizes. Running it briefly every few days keeps the chamber clear and the rotor free, which matters more here because hard water leaves scale on everything it touches.
Switch it off at the wall first and never put a hand into the chamber. Use the hex key in the bottom of the unit to free the rotor, then press the reset button. If it will not free up, stop and call us.
Garbage Disposal Installation — Frequently Asked Questions
Straight answers, without the sales pitch.
How long does fitting a disposal take?
A straightforward like-for-like replacement, with power and switching already in place and a sound sink flange, is typically a single visit of an hour or two. A first-time installation takes longer, because it may need a new flange, changes to the trap arm, and an electrical supply or an air switch under the cabinet. We tell you which one yours is before we start.
Can I use a garbage disposal with a septic tank?
You can, but it needs care. Everything ground up goes into the tank as solids and adds to the sludge layer, so pumping intervals get shorter. If you are on septic, keep quantities small, keep fat and fibrous waste out entirely, and tell us when we quote so we can advise on a suitable unit and sensible habits.
Does my dishwasher need an air gap?
California plumbing code requires the dishwasher drain to be protected against backflow, and an air gap fitted at the worktop is the usual way that is done here. A high loop on its own is what we often find on older installations. We fit what your local code requires and we will tell you if what you have falls short.
What size disposal do I need?
It comes down to how much cooking you do and what the drain looks like downstream. A small household with a short run to the stack is well served by a modest motor. Heavy vegetable prep, a large family, or a long horizontal drain run in an older home wants more power and multi-stage grinding so that particles leave the chamber small.
Should I repair my old unit or replace it?
Jams, a tripped reset, a leaking flange or a failed drain elbow are all worth repairing. A leak from the seam of the body itself, a motor that still hums without turning after being freed, or a grind chamber that is visibly pitted and corroded means the unit is done. We look first and tell you which of the two you have.
Will a new disposal stop my sink blocking?
Sometimes, but not always. If the old unit was grinding coarsely and packing the drain, a better one will genuinely help. If the blockages come from grease build-up, a sagging trap arm or a partly blocked branch further along, a new disposal changes nothing. We check the drain before selling you an appliance that will not fix it.
Do you charge extra for nights, weekends or holidays?
No. We do not add overtime charges, ever. The rate you are quoted is the same whether we come out on a Tuesday morning or at 2am on a holiday weekend.
Are you licensed and insured?
Yes. Power Plumbing USA holds California contractor license #1082507 and carries full liability insurance. All work is performed to California Plumbing Code, and we pull permits where the job requires them.
Where We Provide This Service
We cover 15 Bay Area cities from our Union City base. See the full service area →