Andrew Gabriel wrote:

Sounds like a blocked filter. Have you checked them?
Because they hardly ever need attention with regular house dust,
people often forget them completely. I don't know the DC05, but
dig out the instructions and check all the filters. If it's like
the DC04 in this respect, the main filter is washable under the
tap, but leave it to dry completely in a warm place before putting
it back in again. It could also be a partially blocked hose or
pipe -- again check them all following the instructions.

Motor failure usually results in the motor slowing down and/or
generating a burning smell, neither of which you have described.
However, leaving it to run too hot could well cause motor failure
eventually. There is a thermal cut-out, but don't rely on it.

I think you are spot on. Removed my washable filter and all was OK.

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