phoneticduck

In laymans terms large air handling units temper the air, heating or cooling as required, and it is then ducted throughout the building, with a closed loop feedback system to enable temperature set-points to be maintained. Systems are usually zoned, and balancing can be as much an art as a science, as some zones may compete with each other depending on the set points in each and placement of thermostats etc.

Other systems have permanent chilled and hot water circuits running throughout the building and each individual fan-coil unit draws heating or cooling as required.

Simplest of all are 'split systems' (indoor fan coil unit, linked to an outdoor evaporator/condensers) typical of the sort of thing you see retro-fitted in older apartments/starbucks/shopping malls and these simply work like a refridgerator, with the added feature of being able to run in reverse and provide heat as well as cooling.

I have no idea why I felt the need to write any of this...must be the heat

JohnnyColombia

This is much clearer now thanks, I think you are saying that OP was in the wrong zone.

phoneticduck

Sounds like the OP was feeling too warm all over the terminal. Impossible to make everyone comfortable. Zone issues really only surface in office spaces where people are seating in fixed positions.

I remember some years back when I used to be responsible for Building Engineering Services for a large corporate, there was one facility that accounted for 90% of all 'aircon' complaints. They couldn't agree among themselves about what was comfortable let alone agree with any of my guys.

Answer...we installed thermostats and some conduit going into the ceiling and told them they could adjust the various zones themselves, 'empowering' them.

Cut the complaints almost to zero...not a single one of those thermostats was connected to anything.

lhrsfo

I hate over-zealous aircon like you find in the US. I've always found the temp in T2 to be comfortable- slightly warmer in summer when you are wearing lighter clothes and vice versa in winter.

Reds2011

Most middle east airports are worse IMHO. Even in the cooler months it's like walking into a freezer! Quite an experience in summer to walk from 48C into 18C and can be quite unpleasant if the back of your shirt is sweaty! For our US readers ~120f to 65f.

Discus

One problem at LHR is that all the coolers/fridges in the lounges are not fed cooling from external sources, but have their own systems letting all the warn "exhaust" out in the lounge.

Swanhunter

All round better Terminal.

phoneticduck

we should prevent humans from entering the lounges too, them being the biggest heat source of all.

Analise

Exactly. This isn't rocket science.

I don't remember FRA or AMS not having air conditioning in the summer as they are equally as crowded.

chucko

That was my experience as well yesterday. If your flight is departing from 5B or 5C, the BA lounge in B is much less crowded, has higher ceilings, and seems a bit cooler than in 5 Main.

manda99

I was in the United Club at LHR on Tuesday and it was uncomfortably stuffy - especially after that helluva hike to get there. I didn't notice it to be as uncomfortable in the main terminal areas though.

Adding: And I say this as a person who is normally always cold. I'm the person who keeps a space heater under my desk at the office and am always wearing a hoodie around the office, ha.

JohnnyColombia

On the Thursday in question I went to the F lounge and then had a delay of about 40 mins so went to the lounge above gate A6. Both of those were comfortable and people in the main terminal were wearing sweaters. Yes the B lounge is nice though.

As has been mentioned above people have different preferences when it comes to temperature. I like to be cool but I did not find the terminal uncomfortable. OP clearly is at the cooler end of the spectrum and would not have minded a couple of degrees shaved off.

Given the comments on this thread I'd say LHR got it about right on the day

enviroian

Absolutely 100%. I hate walking around LHR. It's always way too hot and for the life of me I can't understand why they don't turn on the A/C. If they do turn it on whatever temp they have it too is useless so for all intense purposes it's off. By the time you walk the long trek to HEX , tube or another terminal you are sweating.

flatlander

Now, is ridiculous; you do not need to chill any building that cold. That is colder than most people will find comfortable, since most people are comfortable at somewhere around 23C +/-2C that is a good temperature to aim for. So dismissing that and considering only a reasonable interior temperature, T5 is still too hot.

First of all, that's just incorrect. In any building with a lot of heat sources, like people and equipment, or heating due to insolation through large windows, you do need aircon in the UK. That is why any nontrivial building has a significant ventilation and cooling plant; in winter cooling can be done mostly with ambient air exchange, in summer active heat exchange is needed.

Secondly, it is never cold, or even temperate, in LHR T5. That building is too hot in summer, too hot in autumn, too hot in spring, too hot in the day, too hot in the night, too hot in the middle of winter while actual snow is falling out of the sky and the delays are mounting because every aircraft needs decing. All of which I have experienced personally!

I do not understand why T5 is always too hot and while I suspect the entire thermal design may be flawed (in particular may have been based on fewer people and less equipment in shops, restaurants, flight displays, etc), I have not yet seen a coherent explanation of why it is always too hot.

phoneticduck

I've never been too hot, or too cold, in T5. YMMV and that is the main issue with HVAC, everyone has a different sense of what is comfortable for them.