Start with the sound it makes
A disposal tells you a lot before anyone opens the cabinet. A low hum with no grinding means the motor has power but the flywheel is jammed. Silence means a tripped reset button, a dead switch or a failed motor. Grinding or rattling often means a spoon or other foreign object. A loud metallic bang is a bolt or part that has come loose inside.
With the switch off, many jams clear with an Allen key in the hex socket on the bottom of the unit. Never reach into the grinding chamber with your hand, even when the power is off at the switch. Unplug the unit or switch off its breaker first.
Symptoms, causes and what we do
Disposal problems fall into a handful of patterns. This guide matches each one to the usual cause.
| Symptom | Likely cause | Visit usually involves |
|---|---|---|
| Hums but does not spin | Jammed flywheel | Clear the jam, test the motor |
| No sound, no power | Tripped reset, dead outlet or failed motor | Check power first, replace the unit if the motor is gone |
| Leaks from the top | Failed sink flange seal | Reseat the flange with plumber's putty or a new gasket |
| Leaks from the side or bottom | Cracked housing or failed internal seal | Replace the disposal |
| Leaks at the drain pipe | Loose slip nut or worn washer | Tighten or replace the fittings |
| Water backs up into the second sink | Clog past the disposal | Clear the drain line, see drain cleaning |
When to repair and when to replace
Disposals are not built to last forever. A repair makes sense when the unit is newer and the issue is a jam or a loose fitting. These signs point toward replacement.
- A leak from the housing itself. Water leaking from the metal body cannot be sealed. The unit has failed.
- A motor that is burned out. A smell of burnt electrical material and no response from the reset button usually means the motor is gone.
- Frequent jams. If it jams every few weeks, the grinding parts are worn or the unit is undersized for the household.
- The unit is over a decade old and starting to leak. Corrosion in older units tends to appear at several points together.
Double sinks, dishwashers and the plumbing around the disposal
A disposal in a double sink changes how the drain is built. The disposal drains from one basin, and the other basin joins the line beyond it through a tailpiece. If the second basin fills when the disposal runs, the line past the disposal is partly blocked and the grinder is not the cause. Grease and starchy foods are common culprits, which is why we may suggest drain cleaning rather than a new unit.
The dishwasher drain hose connects to a side port on the disposal. The knockout plug in that port has to be removed on a new installation, a step skipped in a surprising number of do-it-yourself jobs. If the dishwasher drains slowly after a disposal swap, that plug is one of the first things we check.
An air gap or high loop on the dishwasher hose keeps sink water from running back into the machine. A plumber installing a disposal should confirm it is in place.
Disposals and older house plumbing in Guilford
Many Guilford homes, especially older ones near the Green and in the shoreline neighborhoods, have kitchen drain lines that were sized and sloped decades ago. Kitchen waste is hard on old pipe, and the drain serving a disposal needs enough slope to carry waste along. If a line is flat or partly collapsed, a new disposal will not fix the slow drain.
Guilford has no municipal sewer, so every disposal in town sends its waste to a septic system. Septic tanks cope poorly with heavy grease and large amounts of ground food waste, and the town requires each system to be pumped every five years. If you run a disposal often, ask your pumper whether your tank needs attention sooner. See also our notes on sewer and septic drain work.
What affects disposal repair and installation price
A disposal visit is quoted around the unit and the plumbing around it, and the price is clear before work starts. Here is what we weigh.
- Horsepower and model.Larger, quieter units with stronger motors cost more than basic models.
- Electrical hookup.A disposal needs a switch and an outlet or hard-wired connection. Adding either needs an electrician or a plumber qualified to do that work.
- Sink and flange condition.Cracked sink flanges and mismatched drain parts add work.
- Dishwasher connection.Reconnecting and adding an air gap or high loop adds a little time.
- Time of day.Emergency visits after hours are quoted at emergency rates.
Insurance usually covers a sudden leak that damages a cabinet or floor but not a worn-out disposal itself. Take photos, keep the old unit if asked and ask your insurer about your coverage. For your actual price, call the 24/7 line.
While you wait for the plumber
A few steps make the visit shorter and safer.
Switch it off
Turn off the wall switch and unplug the disposal or switch off its breaker.
Stop the leak
Close the sink's supply valves if the cabinet is wet, or the main valve if they will not turn.
Empty the cabinet
Move cleaners and boxes out so water does not ruin them and the plumber has room.
Keep hands away
Do not put fingers in the drain, even with the switch off.
Disposal leaking or backed up?
Call the 24/7 line, tell the dispatcher the model if you can see it, and say whether the second sink is backing up too. A whole-house drain problem is bigger than a disposal, and our hydro jetting service is how stubborn grease lines get cleared.
Questions we hear on calls
Yes. A leaking disposal that soaks a cabinet or a drain that backs up into both sinks is handled around the clock.
Not necessarily. A jam is the usual cause. With the power off, turn the flywheel with the hex wrench from below. If it will not free, call.
The drain line past the disposal is partly blocked. A new disposal will not fix that. The line needs to be cleared.
Usually yes. The sink must have the standard drain opening, there must be room under it and a switched power source must be available. Describe the setup on the call.
Grease hardens in the pipe and causes the clogs that give plumbers the most work. Coffee grounds and eggshells collect in traps. Scrape plates into the trash.
It can, and in Guilford every house has one. Ground food adds to the solids in the tank, so ask your septic service about pumping more often if you use a disposal heavily.
Yes. The hose connection, the knockout plug and the air gap or high loop are all checked on any disposal job.
Sources for the local details on this page
The local facts above come from the town's septic system brochure and Guilford plan of conservation and development. Rules and figures can change, so check with the town or state office before you rely on them for a permit or a purchase.