Thank you, Bodd.
There's a saying that misfortunes never come alone. Sad but true.
On the over hand, to be completely honest, this situation with a cylinder.... I don't know how to explain it but it made me feel that... I'm not so alone, I'm gonna be alright. For example, until Sunday I've never spoke to my neighbours apart from saying ''hi'' when we met in the doorway or on the stairs. And still they ready to help me by allowing me to use a shower anytime I need, even offered to help me out if I need to go to Asda or some other place (as they know I don't drive). So, yes, I feel very blessed that I live surrounded by kind and caring people. Will find a way to somehow repay them back.
This morning I've sent a letter to my landlord and my 1rst floor neighbours sent a second one. Both letters need to be signed for when he'll get them. My neighbours asking our landlord to arrange a service for a water cylinder in their flat as it's the same type of cylinder. No dated sticker on theirs but I do understand why they are worried about it. So, fingers crossed, our landlord responds straight away, calls in a qualified engineer, hopefully agrees to pay for all work done. Hopefully, this way (2 flats - 2 cylinders) he will be able to get a discount for himself.