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True Trade Path

Diagnostic guide

Sump Pump Not Working

A silent sump pump during rain risks basement flooding — check power, float switch, and discharge before replacing the unit.

System
Plumbing
Causes covered
7
You can check
5 without a technician

Stop and read this first

  • Never reach into the pit with power on — entanglement and shock risk.
  • Install battery backup for primary pump in storm-prone areas.
  • Discharge must terminate away from the foundation — not into septic.

Work through these in order

Ordered from most to least likely. Working top down means you rule out the cheap, common causes before paying anyone to look at the expensive, rare ones.

  1. Tripped breaker or unplugged cord

    CommonYou can check
    How to check
    No hum from pit. GFCI tripped in basement.
    The fix
    Reset breaker and test outlet. Use dedicated circuit.

  2. Stuck or failed float switch

    CommonYou can check
    How to check
    Pump does not start when water is high. Float hangs or is waterlogged.
    The fix
    Free float or replace switch ($50 to $150).

  3. Clogged intake screen or impeller

    CommonYou can check
    How to check
    Pump hums but does not move water.
    The fix
    Clean screen. Pull pump and clear debris.

  4. Frozen or blocked discharge line

    CommonYou can check
    How to check
    Pump runs briefly then stops. Line exits to frozen yard.
    The fix
    Clear discharge and install freeze guard ($50).

  5. Burned-out motor

    CommonNeeds a pro
    How to check
    Pump silent or smells hot. Unit is 7+ years old.
    The fix
    Replace pump ($400 to $1,200 installed).

  6. Check valve failed — short cycling

    PossibleYou can check
    How to check
    Pump runs every few seconds without much water.
    The fix
    Replace check valve on discharge ($30 to $80).

  7. Undersized pump for water volume

    PossibleNeeds a pro
    How to check
    Pump runs constantly in heavy rain but cannot keep up.
    The fix
    Upgrade to higher GPH pump ($500 to $1,500).

Direct answer

Sump pump silence during rain risks flood — check power, float, and discharge before replacing. Battery backup is cheap insurance.

Severity and urgency

Call today

During active flooding every hour matters.

Cost of ignoring it

One event can exceed $10,000 contents and drywall loss.

How a pro will diagnose it

Replace pump, test float, verify discharge ($400–$1,200 installed).

Prevention and maintenance

  • Annual test pour into pit
  • Clean intake screen
  • Replace every 7–10 years
  • Battery backup
  • Keep discharge ice-free

For trade owners

Pricing this job as a contractor?

Homeowners see national ranges on this page. If you are building the estimate, use the same scope assumptions — then price to burdened labor, overhead recovery and a real margin.

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Find a licensed pro

When you are ready to hire for sump pump not working, start with licence verification — not with whoever answered first.

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Common questions

Could tripped breaker or unplugged cord be causing this?
No hum from pit. GFCI tripped in basement. Reset breaker and test outlet. Use dedicated circuit.
Could stuck or failed float switch be causing this?
Pump does not start when water is high. Float hangs or is waterlogged. Free float or replace switch ($50 to $150).
Could clogged intake screen or impeller be causing this?
Pump hums but does not move water. Clean screen. Pull pump and clear debris.
Could frozen or blocked discharge line be causing this?
Pump runs briefly then stops. Line exits to frozen yard. Clear discharge and install freeze guard ($50).
What is the most common cause of sump pump not working?
Reset GFCI; lift float test.
Can I fix sump pump not working myself?
Some checks are DIY-safe (shutoffs, filters, simple adjustments). Licensed plumber work is required when gas, sewer, refrigerant, or main lines are involved.
How much does professional repair for sump pump not working cost?
Pump $400–$1,200; backup $500–$900.
How urgent is sump pump not working?
Active flooding — now.
Should I shut off water or power for sump pump not working?
Shut off the local supply or breaker when leaks, flooding, sparks, or gas odor are present. If unsure, stop using the system and call a pro.
Will sump pump not working damage my home if I wait?
Moisture-related issues can rot framing and grow mold within 48 hours. Mechanical issues often worsen — seized pumps, cracked heat exchangers, or compressor damage cost far more when delayed.
What should I tell the plumber on the phone?
Describe when it started, what changed (weather, remodel, new appliance), what you already tried, and whether multiple fixtures or zones are affected.
Does homeowners insurance cover sump pump not working?
Sudden pipe bursts are often covered; slow leaks, maintenance neglect, and sewer backups frequently are not. Document with photos and read your policy endorsements.
How do I know the quote for sump pump not working is fair?
Get two written quotes with scope, parts, warranty, and permit line items. Compare to regional mid-range pricing — not the cheapest emergency rate.
How can I prevent sump pump not working from coming back?
Follow the prevention steps on this page: maintenance schedules, avoiding grease and wipes in drains, filter changes, and annual tune-ups where applicable.

Once you know what it is

Step one

Know what it should cost

Get the range before you call, so the first number you hear is not the only number you have.

Step two

Decide repair or replace

On equipment near end of life, the repair is usually the first of several.

Step three

Check the quote

Compare against the typical range and confirm the terms before you sign.

Sump Pump Installation cost guideRepair or replace calculatorEstimate repair costAnalyze a quote

What the fix costs

Tools for this decision

Other symptoms