Running toilet in the suite restroom

What this error means

Fluidmaster's own guidance: replace the flapper first — it's the most common cause, a $12–30 part that degrades until it can't seal. The other documented suspects: water level set too high (spilling into the overflow tube continuously), a failing fill valve, or a snagged chain. A running toilet wastes shocking volumes — this is a same-day fix, not a someday fix.

Symptoms

• Water sound that never stops
• Tank refilling by itself periodically
• Handle-jiggling as institutional practice

Try this first (safe DIY steps)

1. Dye test: food coloring in the tank; color in the bowl without flushing = flapper leak
2. Replace the flapper (match size, 2" or 3") — tool-free, ten minutes
3. Check water level: should sit ~1 inch below the overflow tube top; adjust the fill valve float
4. Chain: one small loop of slack, no snags
5. Still running: replace the fill valve ($12–30, twenty minutes)

Safety: power off before any physical intervention. Never bypass covers or interlocks — fuser areas run hot enough to burn.

When to call a technician

A plumber's running-toilet visit runs $130–300. The parts are under $30 and the job is genuinely easy — this is the definitional DIY plumbing repair.