Step 1 If you have shut off the water supply line then turn on water and look inside the tank. 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. How To Fix A Running Toilet With A Ball Float A Detailed Guide Leaky Toilet Toilet Dual Flush Toilet When a Glacier Bay dual flush toilet keeps running it damages your humble home and also increases the water bill. Dual flush toilet running . A dual-flush toilet presents a homeowner with the ability to conserve water in the bathroom. To solve this problem you have to empty the toilet tank completely. The two main parts to focus on are the fill valve and the flapper. Symptoms of Occasional Leaking or Running. The toilet has two flush options. With your left hand grab the cap and at the same time place your thumb on the side of the plastic arm. The float rests on the water and moves up. Dysfunctional flapper is the main cause...