Praying Salah With Wudu When Ghusl Is Obligatory
Tayammum can be done in place of both Wudu and ghusl in cases where an undue difficulty makes it difficult to perform regular Wudu or Ghusl. For instance, when there is water shortage or limited water, when the person is sick or travelling etc. If there is no such issue genuine issue, then such a prayer will not be valid where Wudu is done in place of ghusl.