Changing and Washing the Filters on a Dyson DC27
If your Dyson DC27 is to remain in good working order, you need to wash the filters every few months. If they are in a particularly bad way, or you have used your machine to vacuum up fine dust such as plaster dust, you may be better advised to swap them altogether.
Many people do not know that their Dyson DC27 has filters that must be washed. If your Dyson DC27 is cutting out or overheating, it is likely that the filters need changing. Dysons have what is known as a thermal cut out on the motor that causes the motor to shut off if it gets too hot. This is a design feature to protect the motor. The reason that the motor gets hot is there is not enough air passing through there to keep it cool. The reason there is not enough air passing through there is because the filters are blocked.
Make sense?
So all you need to know now is what to do with them to save you a few Pounds, Dollars or Euros in the repair shop. Here is a Dyson Medic photo tutorial to help you do just that.
Start by removing your pre-motor washable filter by depressing the two buttons indicated by the arrows below:
It now can be removed like this:
The filter easily comes out of the housing like so:
Now it can be washed. Dyson tell you to only run it under a cold tap. I suggest that this method is close to useless; and putting it in the washing machine will be just fine. 30 degrees will be great (not too hot or it will shrink). I prefer to give them an initial dowsing with a pressure washer first; that gets the real gunk off. After that dry it out PROPERLY on a radiator or in a warm place. DO NOT refit while it is still damp – that will kill your Dyson stone dead. At least 24 hours in a warm place is needed.
Now on to the other filter. The post motor filter. First, remove your cyclone unit by pressing the red button as indicated below.
After this, open the bottom flap using the clip indicated below:
Now it will look like this:
The filter can now easily be removed:
I do not recommend putting this one in the washing machine. This one has a more delicate paper element that Dyson suggest can be washed up to ten times before it needs replacement. If you have access to any, compressed air is best to start with. Follow this by a pressure washer if you have one; if not, any strong water flow will do. Wash it as best as you can and dry it as you did with the other filter.
Refit both your filters only when they are completely dry. You should now be good to go again! 
If your filters are beyond washing and need replacing, Dyson will charge you an arm and a leg for them. Go >>here<< to buy them instead.
I have read your instructions for changing pre filter on dyson dc27 but the cover on my dyson dc27 is different. The cover is the same grey as the body of the machine. It appears to be hinged at the back in front of upright section and has 3 x thin rectangular lugs around the side of the filter container – one on either side and one in the middle. Please can you help me with how to remove this?
Many thanks.
My Dyson is the same Carol and I cannot remove the second filter. Did you get a response to your query?
This is an alternative fitting and not so user friendly! However, it’s fairly easy to open. You need a broad tip flat screwdriver. Insert it under each of the clip housing bars in turn and twist while pushing out the barbed cip. There are 3 to do and its fidley and requires some concerted pushing and wriggling. Note that the rear of the lid is a sort of unsecured hinge that will eventually separate from the body of the machine. The lid of the compartment will come away eventually and inside it is as described for the alternative construction.
Thanks for the info. This was very helpful in removing the post-motor filter from my Dyson DC27, which seems to be the same model. As you say, Dyson do not seem to have designed this to be opened easily. I was fearful of cracking the cover, but was eventually able to use a large screwdriver to prise the lid away from and over the top of each lug. I didn’t manage to wiggle the lid off completely, but with difficulty managed to remove the filter with the lid still on. My filter was black when I removed it, and washing it in cold water didn’t seem to help, so I will order a new one. It seems strange that this filter cannot be maintained as easily as the pre-motor filter, but hopefully Dyson have corrected this in newer models.