Hot water

The weather has finally turned pleasant - after 20 days of rain, rain, and more rain! But I am not convinced that the sun is here to stay. Anyway, it was absolutely fascinating - but two days ago my friend wanted to take a hot shower at my place, and once again there was no hot water. This was - for me - the last straw! I have spent the last two months trying to fix the water problems in my apartment. First I woke up at midnight to neighbors banging on my door because I had flooded the whole building when a hose broke off the filter to my washing machine. The next week, the sink in my kitchen broke (another cheap Chinese hose) and I again flooded the downstairs neighbors. Then another pipe in the bathroom was leaking - and all the while the hot water boiler in the shower was leaking rust. Finally, I decided to suck up the price of a new boiler in the case my landlady won't replace the broken thermex when she returns from vacation (as she was originally arguing that since I am living in the apartment long-term, it's my apartment and I am responsible for any and all repairs). The "santeknik" (plumber) put in a new thermex and after that for a week, I would have hot water one day and cold water only the next. Finally, my friend, who wanted a hot shower, had a brilliant idea and turned on the hot water faucet(tap) running between the thermex and the shower head. BUT WHAT KIND OF santeknik, who knows I want hot showers would leave it closed???