Hi, I need to temporarily remove a radiator in the bathroom. All the stuff I\\\'ve read online says there will be a manual control valve at one end, and a locksheild valve at the other, which i should be able to remove the plastic cover from. However, both valves look exactly the same, like temperature controls with a + and -, and i can\\\'t remove the plastic cover from either one... I\\\'ve compared to other radiators in the house, some of which do have removable plastic covers. what do i do if i can\\\'t remove the cover - just turn it clockwise to close it? please help! thanks