Looks like the landlady is NOT EVER going to fix the central heating, so it’s now up to several space heaters and these guys. Still do not comprehend how this is to her benefit because, if I leave tomorrow, she’ll have to repair the whole central unit and much more. And she may end up with someone who doesn’t maintain the apartment as well as I do, who doesn’t pay on time, etc etc. Anyhow, for now we are all cosy.