Repair when Flushing
Toilet Running Constantly
When the toilet is constantly running we must first find out if you have a fill valve issue or a flapper/flush valve issue.
Step 1 – If you have shut off the water supply line, then turn on water and look inside the tank. Determine if the water level is rising so high it is draining into the overflow pipe. If the answer is yes then follow the steps for cleaning the fill valve.
Step 1A – If flushing debris (Cleaning Solution) does not resolve the issue; Replace the fill valve. We recommend installing the 400H PerforMAX toilet fill valve.
Flushing Debris (Cleaning Solution):
It is possible for dirt and debris to lodge itself inside the valve. This can happen any time the water is on and may happen after a new installation, a few days later or even months and years after installation.
Follow these steps to clean the valve:
Turn off water and flush the toilet.
Reach into the tank with your right hand and lift up the float cup and grip the gray shaft and hold it in that position (see photo below).
With your left hand grab the cap and at the same time place your thumb on the side of the plastic arm.
Twist both the cap and plastic arm counterclockwise 1/8th turn. Press down on the cap while making a quick twisting motion.
Lift up on cap and move away from top of valve body. Using a cup hold the cup upside down over the exposed opening of the valve and turn on the water supply full force for 10-15 seconds. Look inside valve to ensure no debris is left inside the valve.
Reverse steps to place top back on the valve. Turn on water and flush toilet to ensure problem has been resolved.
Video: How to Fix a Running toilet
If this procedure does not resolve the issue then replacing the fill valve should resolve the issue. We recommend using the 400H PerforMAX toilet fill valve.
Step 2 –With the tank full of water turn off the water to the toilet and mark the current water level inside the tank. Wait a period of time 10-15 minutes and note if the water is draining down from your mark. If it drains down replace the flapper first as this is the most common problem. To determine whether you need a 2″ or 3″ flapper, please click here: Determine size of flapper
If you need a 2″ toilet flapper, we recommend the 502 toilet flapper
Step 3– If you replace the flapper and the toilet continues to drain down (repeat step 2 if necessary) then we recommend replacing the flush valve as this will ultimately stop the constant draining of water from the tank to the bowl. We recommend the K-507A-008 flush valve if you have a 2″ toilet or the 540AKR flush valve if you have a 3″ toilet. To view all the flush valves, please click here: Flush Valves
Step 4 – If at any time the toilet is running and you see water on the floor immediately turn off water and look inside the tank to see if the water is coming from the lid or tank lever area. Replace fill valve and replace flush valve. The flush valve is set to the wrong height or may be blocking the path of the water to drain safely into the toilet bowl. If water is draining down and water is coming out from the bottom of the tank change tank bolts and washers.
If you need to replace any of the toilet parts, why not get Fluidmaster’s Everything Kit includes everything you need to fix your toilet in one purchase?
If you are in the U.S. and have a 2″ flush valve toilet, we recommend the 2″ Everything Kit
If you are in the U.S. and have a 3″ flush valve toilet, we recommend the 3″ Everything Kit
If you are in Canada and have a 2″ flush valve toilet, we recommend the 2″ Everything Kit
To download our free guide to fix common toilet problems please click here: Fluidmaster Toilet Repair Guide