WiremanWireman · Outdoor circuit dead after rain: troubleshooting for electricians · 2023 NEC ·
Outdoor circuit dead after rain
Find the tripped GFCI, then find where the water is getting in.
Before you start
How much electrical experience do you have?
This sets how much detail each step shows. You can change it any time.
Showing detail
How it works
Outdoor receptacles must be GFCI protected, and the reset is often somewhere else: a garage, bathroom or basement receptacle, another outdoor receptacle, or a GFCI breaker. When water gets into a receptacle, a cover, a cord connection or a buried box, a tiny current leaks to ground and the GFCI shuts the circuit off. That’s the GFCI doing its job, so the fix is to find and stop the water, not to replace the GFCI.
Every question and answer in this guide. Tap “Step by step” to walk through it.
- Have you found the GFCI that controls it?
- Found and reset, works nowGFCI tripped from moisture
- Found it, won’t reset or trips againUnplug everything outdoors on that circuit. Does the GFCI reset and hold?
- Holds with everything unpluggedWet cord or plugged-in device
- Still trips or won’t resetDoes it reset and hold once things dry out (ask the customer about past episodes)?
- Yes, resets when dryTest: Inspect the outdoor boxes
- Water or corrosion in a boxWater in an outdoor box
- Boxes are dryTest: Insulation-test the outdoor wiringExpect: Hundreds of megohms or more. Under about 1 MΩ is a problem.
- Low readingDamaged or wet underground wiring
- High readingFailed GFCI
- No, stays trippedTest: Insulation-test the outdoor wiringExpect: Hundreds of megohms or more. Under about 1 MΩ is a problem.
- Low readingDamaged or wet underground wiring
- High readingFailed GFCI
- Yes, resets when dryTest: Inspect the outdoor boxes
- Can’t find a GFCI anywhereHidden GFCI or no power