CLR to Clean Washing Machines

CLR is a product formulated to remove calcium, lime and rust, hence its acronym. It requires no scrubbing as it dissolves deposits automatically. Use it as a general washing machine cleaner to remove hard water deposits as well as other residue. The manufacturer also claims it's effective for removing the moldy smell from front loading washers. Cleaning directions do vary based on whether you are cleaning a front- or top-loading washer. Follow the specific directions for the washer type to use the product effectively and safely.

Toxicity Issues

Consider the chemical makeup of CLR when deciding whether to use it to clean your washing machine. The makers of CLR say it is septic safe, claiming by the time CLR moves into your septic system the water has neutralized it. CLR is non-abrasive and contains no bleach, phosphates or ammonia, but it does contain three types of acids: sulfamic acid, citric acid and glycolic acid. These acids are corrosive if left to stand in your washing machine.

Top-Loading Machines

To use CLR in a top-loading machine, run the machine on the main wash cycle, but keep it empty. Wait until the cycle stops and is about to start agitating. Then add 1/2 cup of CLR to the drum. Complete the cycle and run an additional full cycle to rinse the machine thoroughly.

Front-Loading Machines

To use CLR in a front-loading machine add the 1/2 cup of CLR to the drum at the beginning of the main cycle. Since a front-loader uses less water than a top-loader, add another three cups of water to the drum after you pour the CLR in. Run the full cycle and then run a second full cycle to rinse the drum thoroughly. After the cycle finishes, wipe the seal and door to remove moisture. The makers of CLR recommend cleaning your front-loader about once a month to reduce mold buildup and odors.


Wear rubber gloves when using CLR to clean your washing machine. Open a window or door when using CLR; use the product only in well-ventilated areas. Do not mix CLR with other cleaners or bleach. Refrain from putting CLR into a spray bottle; the spray could drift back on your clothes or into your eyes. Do not use CLR directly on clothing; it can stain the fabric.