Hotpoint WD420 Lights 3 & 4 flashing Home › Forums › Trade Technical & Spare Parts Forums › Trade Technical Enquiries › Hotpoint WD420 Lights 3 & 4 flashing This topic has 1 reply, 2 voices, and was last updated 7 years ago by folleyball. Viewing 2 posts - 1 through 2 (of 2 total) Author Posts April 3, 2019 at 9:05 pm #95706 folleyballParticipant Just checking does this mean change the heater sensor on the heater element or the dryer unit? April 4, 2019 at 12:08 pm #461129 iadomModerator I think F03 is the wash heater side. Jim. Author Posts Viewing 2 posts - 1 through 2 (of 2 total) You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In