Context :

Aims : In our series of papers presenting the Herschel imaging of evolved planetary nebulae , we present images of the dust distribution in the Helix nebula ( NGC 7293 ) .

Methods : Images at 70 , 160 , 250 , 350 , and 500 \mu m were obtained with the PACS and SPIRE instruments on board the Herschel satellite .

Results : The broadband maps show the dust distribution over the main Helix nebula to be clumpy and predominantly present in the barrel wall .
We determined the spectral energy distribution of the main nebula in a consistent way using Herschel , IRAS , and Planck flux values .
The emissivity index of \beta = 0.99 \pm 0.09 , in combination with the carbon rich molecular chemistry of the nebula , indicates that the dust consists mainly of amorphous carbon .
The dust excess emission from the central star disk is detected at 70 \mu m and the flux measurement agrees with previous measurement .
We present the temperature and dust column density maps .
The total dust mass across the Helix nebula ( without its halo ) is determined to be 3.5 10 ^ { -3 } M _ { \odot } at a distance of 216 pc .
The temperature map shows dust temperatures between 22 K and 42 K , which is similar to the kinetic temperature of the molecular gas , confirming that the dust and gas co-exist in high density clumps .
Archived images are used to compare the location of the dust emission in the far infrared ( Herschel ) with the ionized ( GALEX and H \beta ) and molecular ( H _ { 2 } ) component .
The different emission components are consistent with the Helix consisting of a thick walled barrel-like structure inclined to the line of sight .
The radiation field decreases rapidly through the barrel wall .

Conclusions :