--- title: "Toilet Keeps Running: Causes & Fixes | Dominick Plumbing" description: "A running toilet wastes up to 200 gallons a day. Here are the 6 causes a Scottsdale plumber sees every week — and which ones you can fix yourself." lang: en json-ld: | [ { "@context": "https://schema.org", "@type": "Plumber", "@id": "https://dominickplumbing.com/#business", "name": "Dominick Plumbing", "legalName": "Dominick Plumbing LLC", "image": "https://dominickplumbing.com/apple-touch-icon.png", "logo": "https://dominickplumbing.com/apple-touch-icon.png", "telephone": "+1-623-323-4538", "email": "info@dominickplumbing.com", "url": "https://dominickplumbing.com", "priceRange": "$$", "foundingDate": "2021-01-01", "identifier": "Arizona ROC 350819", "hasCredential": "Arizona ROC #350819", "address": { "@type": "PostalAddress", "addressLocality": "Scottsdale", "addressRegion": "AZ", "addressCountry": "US" }, "geo": { "@type": "GeoCoordinates", "latitude": 33.4942, "longitude": -111.9261 }, "areaServed": [ { "@type": "City", "name": "Scottsdale, AZ" }, { "@type": "City", "name": "Paradise Valley, AZ" }, { "@type": "City", "name": "Phoenix, AZ" }, { "@type": "City", "name": "Fountain Hills, AZ" }, { "@type": "City", "name": "Cave Creek, AZ" }, { "@type": "City", "name": "Carefree, AZ" }, { "@type": "City", "name": "Tempe, AZ" }, { "@type": "City", "name": "Mesa, AZ" } ], "aggregateRating": { "@type": "AggregateRating", "ratingValue": "5.0", "reviewCount": 200, "bestRating": "5" } }, { "@context": "https://schema.org", "@type": "BlogPosting", "@id": "https://dominickplumbing.com/toilet-keeps-running-causes-fixes-scottsdale#article", "mainEntityOfPage": { "@type": "WebPage", "@id": "https://dominickplumbing.com/toilet-keeps-running-causes-fixes-scottsdale" }, "headline": "Toilet Keeps Running: Causes & Fixes", "name": "Toilet Keeps Running: Causes & Fixes", "description": "A running toilet wastes up to 200 gallons a day. Here are the 6 causes a Scottsdale plumber sees every week — and which ones you can fix yourself.", "articleSection": "Toilets", "datePublished": "2026-05-24", "dateModified": "2026-05-24", "inLanguage": "en-US", "url": "https://dominickplumbing.com/toilet-keeps-running-causes-fixes-scottsdale", "wordCount": 487, "author": { "@type": "Organization", "name": "Dominick Plumbing", "url": "https://dominickplumbing.com" }, "publisher": { "@type": "Organization", "name": "Dominick Plumbing", "url": "https://dominickplumbing.com", "logo": { "@type": "ImageObject", "url": "https://dominickplumbing.com/favicon.ico" } } }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://dominickplumbing.com/" }, { "@type": "ListItem", "position": 2, "name": "Blog", "item": "https://dominickplumbing.com/blog" }, { "@type": "ListItem", "position": 3, "name": "Toilet Keeps Running: Causes & Fixes", "item": "https://dominickplumbing.com/toilet-keeps-running-causes-fixes-scottsdale" } ] } ] --- [![Dominick Plumbing](/assets/dominick-plumbing-logo-kbhHe4U8.png)](/) [Home](/) [Services](/services) - [Water Heater Install & Repair](/services/water-heaters) - [Tankless Water Heater Installation](/services/tankless-water-heater-installation-scottsdale) - [Water Softeners](/services/water-softeners) - [Reverse Osmosis Systems](/services/reverse-osmosis) - [Pipe & Slab Leak Repair](/services/pipe-leak-repair) - [Automatic Leak Detection & Shut-Off](/services/leak-detection-shutoff) - [Drain Cleaning & Hydrojetting](/services/drain-cleaning) - [Toilet Replacement](/services/toilet-replacement) - [Faucet Replacement](/services/faucet-replacement) - [General Plumbing Repair](/services/plumbing-repair) - [View all services →](/services) [Service Areas](/areas) - [Scottsdale](/areas/scottsdale) - [Paradise Valley](/areas/paradise-valley) - [Phoenix](/areas/phoenix) - [Fountain Hills](/areas/fountain-hills) - [Cave Creek](/areas/cave-creek) - [Carefree](/areas/carefree) - [Tempe](/areas/tempe) - [Mesa](/areas/mesa) - [All service areas →](/areas) More - Recommended Products - [TOTO Toilets](/products/toto-toilets) - [Navien Tankless Water Heaters](/products/navien-tankless-water-heaters) - [Trutankless Electric Tankless](/products/trutankless-electric-tankless-water-heaters) - [Encore Reveal Softener](/products/encore-reveal-water-softener) - [Encore IonX5 Conditioner](/products/encore-ionx5-water-conditioner) - [Waterdrop Reverse Osmosis](/products/waterdrop-reverse-osmosis) - [LeakSecure Leak Detection](/products/leaksecure-leak-detection) - [All recommended products →](/products) - Company - [Blog](/blog) - [About](/#trust) - [Contact](/contact) [(623) 323-4538 Call ](tel:6233234538) [All articles](/blog)Toilets # Toilet Keeps Running: Causes & Fixes May 24, 2026 4 min read ## Why your toilet keeps running A toilet that runs constantly — or cycles on and off every few minutes — can waste **up to 200 gallons of water a day**. In Scottsdale's tiered water rates, that's a real number on your bill, fast. The good news: most causes are cheap to fix, and you can DIY several of them. Here are the six most common causes, in the order a plumber checks them. ## 1\. A worn or warped flapper The rubber flapper at the bottom of the tank seals water in. Over time — especially in Scottsdale's hard, chlorinated water — it warps, curls, or gets coated in mineral buildup and stops sealing. **Fix:** Shut off the angle stop, flush, replace the flapper ($5–$15). Match brand if possible — Korky, Fluidmaster, and Kohler all use slightly different shapes. ## 2\. Chain too tight or too loose A chain with no slack holds the flapper slightly open. A chain with too much slack catches under the flapper. **Fix:** Adjust so there's about a half-inch of slack when the flapper is closed. ## 3\. Fill valve set too high If water trickles into the overflow tube nonstop, your fill valve is set above the overflow level. **Fix:** Lower the float so water stops about 1 inch below the top of the overflow tube. Most modern Fluidmaster valves adjust by twisting the top. ## 4\. Failed fill valve Fill valves wear out — usually 5–10 years in Scottsdale's hard water. Symptoms: phantom flushes, hissing, water level that creeps up, or a valve that won't fully shut. **Fix:** Replace the entire fill valve ($15–$25 for parts). DIY-friendly with a wrench and 20 minutes. ## 5\. Mineral buildup on the flush valve seat The plastic ring the flapper sits on collects calcium and chlorine residue, breaking the seal even with a brand-new flapper. **Fix:** Shut off water, drain the tank, gently scrub the seat with a Scotch-Brite pad. Don't sand it. ## 6\. Cracked overflow tube or flush valve If you've replaced the flapper, the fill valve, and the seat is clean and it _still_ runs, you likely have a hairline crack in the flush valve or overflow tube. **Fix:** Replace the entire flush valve — or honestly, at this point, the smarter move is a new toilet. Once two or three components have failed, the rest are close behind. ## When to just replace the toilet - The toilet is 20+ years old (uses 3.5+ gallons per flush) - You've replaced internals twice in 2 years - The porcelain is cracked or stained beyond cleaning - You're still using a pre-1994 high-flow model A new 1.28 GPF toilet pays for itself in water savings in 3–5 years for a typical Scottsdale household. ## Related services from Dominick Plumbing - [Toilet replacement and installation](/services/toilet-replacement) - [General plumbing repair](/services/plumbing-repair) Licensed in Arizona (ROC #350819). Call (623) 323-4538 for same-day toilet service. ### Need a licensed Scottsdale plumber? Dominick Plumbing — Arizona ROC #350819. Honest estimates, no surprises. [Call (623) 323-4538](tel:6233234538) ## Keep reading - [Toilets ### Comfort-Height Toilet Upgrade Guide Comfort-height toilets sit 2 inches taller than standard. Here's who actually benefits, who shouldn't bother, and what to look for when replacing yours. ](/comfort-height-toilet-upgrade-scottsdale) - [Toilets ### One-Piece vs Two-Piece Toilets Stuck between a sleek one-piece and a traditional two-piece toilet? A Scottsdale plumber breaks down cost, cleaning, performance and resale impact. ](/one-piece-vs-two-piece-toilet-scottsdale) - [Drain Cleaning ### What Is Hydrojetting and When Do You Need It? What hydrojetting is, the kitchen drain problems it actually fixes, and 2026 costs to hydrojet individual drains in Scottsdale — from a licensed AZ plumber. ](/what-is-hydrojetting-and-when-do-you-need-it) - [Leak Detection ### Whole House Leak Detection System Installation Guide How whole house leak detection system installation works in Scottsdale: placement, prep, 2026 costs, timeline, and calibration from a licensed plumber. ](/whole-house-leak-detection-system-installation) ![Dominick Plumbing](/assets/dominick-plumbing-logo-kbhHe4U8.png) Family-owned, licensed plumbers serving Scottsdale and the entire Valley. Clean water. Pure confidence. Licensed · Bonded · Insured ## Contact (NAP) - Dominick Plumbing - Scottsdale, AZ Arizona ROC #350819 - [(623) 323-4538](tel:6233234538) - [info@dominickplumbing.com](mailto:info@dominickplumbing.com) ## Service Areas - Scottsdale, AZ - Paradise Valley, AZ - Phoenix, AZ - Fountain Hills, AZ - Cave Creek, AZ - Carefree, AZ - Tempe, AZ - Mesa, AZ © 2026 Dominick Plumbing. All rights reserved. [Privacy & Cookies](/privacy)Scottsdale, AZ · (623) 323-4538 We use cookies to keep this site working and to understand how it's used. You can accept all cookies or reject non-essential ones. See our [Privacy Policy](/privacy). Reject non-essentialAccept all