Why Does a Basement Commode Lose Water When One Flushes?

Water Shut-off Valve

• Check the toilet's water shut-off valve. The shut-off valve is located at the bottom rear of the basement commode. If the valve is incorrectly adjusted, water will not properly flow to the toilet in order to refill it following a flush. Use your hands to turn the valve counterclockwise to open the valve further in order to allow more water flow to your toilet. This may fix the commode's water problems immediately. Test the adjustment by flushing the commode and checking the water refill level.

Water Tube Coupling Adjustment

• Check the water tube where it enters the coupling along the left side of the commode. The tube meets the coupling about halfway up the toilet's bowl section. If this coupling is leaking at all, proper water flow to the toilet will be adversely affected. Tighten the coupling over the water tube by twisting the coupling with clockwise turns using an adjustable wrench.

Flapper Valve Replacement Preparation

• Return to the water shut-off valve on the rear of the basement commode if the water level remains a problem. Turn the valve clockwise as far as possible in order to cut the flow of water to the toilet. Flush the toilet and hold down its handle to drain the remaining water from the commode. Lift off the toilet's tank lid at the top of the toilet when the water has been drained.

Flapper Valve Replacement

• Look inside the commode's drained tank for the circular flapper valve. It is connected to a chain hanging from the flush handle. Use your hands to remove the end of the chain from the flapper valve, then pull the valve out. Set a new flapper valve in its place, and reattach the handle's chain to the same spot on the replacement valve.

Refilling the Commode

• Set the tank's lid back into place on the commode. Turn the water shut-off valve counterclockwise again to allow water flow to resume. Flush the basement commode and wait for the water to refill. Water loss will no longer be an issue.