Hi all. Moved in to rented property recently. Got to grips with preset timings on heating, no probs. Hot water timings are seperate but didn't use them as water was perfectly hot without preheat. Recently hot water has not been great so began to use the preheat, however it heats the rads also even though the heating is defo in off setting. Any suggestions, some setting or other I can sort myself or bigger issue? Thanks for any help.