There are some conditions that render dry ablution invalid such as the presence of water or anything that invalidates ablution. It also becomes invalid if the reason for it no longer exists such as illness. 

Conditions rendering dry ablution invalid

1-Dry ablution is invalidated by anything that invalidates normal ablution.

2-The availability of water, if the dry ablution has been resorted to for the unavailability of water. The Prophet (peace be upon him) told his Companion whom he had advised to resort to dry ablution:

‘If you find water, then perform the ablution.’

3-Dry ablution also becomes invalid if the reason for it, such as illness, no longer exists.