I've stayed at CitizenM many times before over the past 5 years, at different locations but mostly this shoreditch one. This trip I decided to bookend a 3 week trip with 3 days there just to end the trip on a nice, simple, comfortable tip (no dealing with an unknown airbnb which might have issues) Unfortunately it was a week of unseasonable warmth in the UK, and the rooms were very stuffy. The first one had fully unfunctioning AC / 0 ventilation. They did a system reset which let a tiny bit of air in, enough to sleep the first night. But by the end of the second day it either stopped working or wasn't good enough, and felt both hot and humid in the room, so I had to pack up and switch rooms. The new room had a bit better temperature control but again wasn't comfortable at the hottest points. At no point was it possible to get any decent amount of 'ventilation" going in the room, (any air below a tiny, almost negligible flow from the vents), hence a matter of waiting hours for things to cool down. This might not be a problem if there were windows to open, but since every CitizenM room has you hermetically sealed in a glass box like some kind of bug on display, there's nothing to do but to lay there and suffer. One of the elevators was broken / under construction, meaning longer wait times. Another elevator had a broken screen on all levels, Construction (presumably on the elevator? maybe the roof as well) was quite loud during the days and interrupted business. calls I tried to take in my room. Staff did their best to accommodate, were very nice about switching room + resetting the system (no support staff available to look into the cooling system) + comped me a drink when it got really bad one night while I waited for them to investigate/switch rooms, but this was a poor end to my trip and I regret picking CitizenM.