When it comes to cleaning a Down filled sleeping bag; you are going to want to do this from a Laundromat (if you happen to have one nearby). You might be able to do this at home for some smaller sized bags; but, that too isn't recommended. Your home washer and home dryer are not quite rugged enough to clean your sleeping bag, so your best option is to go to a laundromat for their industrial-sized equipment and a front-loading washer. DO NOT use a top-loading washing machine with an agitator column—as the bag could get twisted around and/or torn. If you are like the average individual, you likely haven't washed you sleeping bag(s) in years and it might be time to give 'em a thorough cleaning. This is particularly best done after the camping season is done and before storage as to prevent trapped moisture from ruining your sleeping bag during any storage time. You can get a sleeping bag professionally laundered at some tech cleaners; but it's also pretty easy to do the cleaning yourself. Here is what you'll need to consider and do. If you're using a zero-degree or alpine bag with high-quality insulation, large baffles or hefty loft, it is recommend putting the sleeping bag in a larger washer. The large drum will help expel water. If you over-stuff your home washer or dryer, these machines can't do the same tasks as efficiently.
Using the proper sleeping bag cleaner
Never, ever dry-clean your sleeping bag, nor wash it with regular laundry detergent. This is where most people go wrong when it comes to DIY cleaning. If you use standard household detergent cleaners, your down sleeping bag typically ends up with “down clumping.” Read the care instructions label provided on the product. If the tag is missing, check the manufacturer's website for cleaning guidelines.
For a down filled sleeping bag you will want to wash it with a down cleaner specially formulated for down feathers and fibers. A good product to use is Nikwax Down Wash Direct – click here to purchase. or https://amzn.to/3X8gBUE Nikwax offers other products including Nikwax Down Proof Waterproofing, Nikwax TX. Direct Spray-On and Nickwax Tech Wash…
Washing and drying your sleeping bag
The care instructions on the sleeping bag should cover the basic cleaning, water temperature and spin cycle requirements. Typically you'll want to use either cold or warm water—never hot—and put it through a second rinse cycle.