How do you clean a down blanket?

Try an enzyme product, similar to the old standby, Nature’s Miracle.

Apparently the biggest threat from machine washing is to your washing machine

You could try dry cleaning.

Dry cleaners. That’s the only way I wash my down comforter.

Washing down sleeping bags is part of maintenance of the bag. Body oils and sweat work their way into the down and degrade the insulation properties of the down. I clean mine at the laundromat in the front loading kind of machine with mild detergent like woolite. Dry in a big tumble dryer at low heat with a couple of tennis shoes (hopefully clean ones) and that will re-fluff the bag. I know its not a comforter, but probably pretty close.

When summer comes, be sure to set it outside all day on the sunniest day there is. then the next day bring it outside again and flip it over. The sun kills gross stuff.

I suggest a combo’ of what @majorrich and @Kraigmo have written. I’ve owned down sleeping bag, down pillows and down comforters all my life, grew up with the stuff. The giant front loading washers are great for the laundering then hang or lay it out after to dry in the sun since sunlight really does a great job with smells. Finish up by putting it in a dryer with the sneakers so the dried down can be beaten loose and fluffed again.

Use Prosolve. It’s a carpet cleaner spray on that fabulously cleans clothes, tableclothes[red wine], upholstery and down duvets[mustard stain from eating a hot dog in bed!]. You may have to spray a few times. You don’t have to scrub much just let it work. Magic!

My son used to have a down winter coat, and the instructions said to do what @majorrich said, using the tennis shoes to puff it back up. I did, however, just use my own washer and dryer.

I too recommend professional dry cleaning first… but if you want to save some bucks and have a big enough washer/dryer…. go for it:

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