Hi

First of all this is no big problem only an observation that is a little strange to me. A/C temperature.
I do not want to start some crazy bug discussion only a simple question why?

How is it possible that the inlet air temperature in the A B C .... cabins are higher then the master temp?
Master is 24 Celsius but the other is 26, Magenta color. In general this is very warm like a day at the beach. And when I lower
master to let say 23 or 22 the compartments are cooled down to that but after a while they are raised again.
In my car I have it set to 21-22 year around, at home 21. So 24-26 is far to warm for me in travel.

If this is a bug after all then it is a very tiny minor one, only at some TODO list. That is enough for me.
I'm only thinking about how my AI passengers feel.

 

 

I've been looking for an answer to this for years, Per

It is possible for the Purser/Cabin Services Manager/ chief cabin attentant to vary individual zone temperatures (a few degrees) from the Master, using a control panel in the cabin. Also, the automatics, after the aircraft reaches cruise altitidue, gradually increase the cabin temperatures for a period of 2 hours. Normally there is very low humidity in the cabin at higher altitudes. To make passengers more comfortable in these conditions (and I'm not sure if it actually works), but I was told that if the cabin temperatures are increased, people sweat more... and, somehow, our bodies interpret this as higher humidity). I'm not sure if this "comfort correction bias", as it is known, is active on all aircraft (I have this vague recollection that some aircraft don't have it or it has been deactivated on some aircraft). At Top of Decent, the bias will be ramped out within 5 minutes.

However, my manuals don't tell me if the magenta targets (master or individual zones) are changed as a result of the Purser input or the comfort correction bias, but moving the master control in the cockpit should (at least) reset the comfort correction bias. 

Pilots?

Cheers

JHW

I've noticed the same issue, any solutions?

The packs works to the coldest selected temperature of the zones. the other zones are warmed up with trim air.

Not a bug, an actual Boeing feature :)

So I should talk to my AI FA's and ask what they are doing? :-) Having a beach party or what.....?  :-)

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The packs works to the coldest selected temperature of the zones. the other zones are warmed up with trim air.

 

 

Don't confuse what you are seeing in the screenshot and normal zone temperature control.

Adding to your comment... The Zone Temperature Controller uses the target temperatures set by the cockpit and Purser temperature control panels and compares this with the actual temperatures in those zones. The ZTC then sends the demand to the pack controllers. If a cold temperature is selected in a normally cold zone (e.g. zone A), then the pack won't have to do much work (for that zone). So, strictly speaking, the packs "work" to demand, not to the coldest selected temperature.

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So I should talk to my AI FA's and ask what they are doing? :-) Having a beach party or what.....?  :-)

Perhaps, but I think this is more a case of comfort correction (which is limited to a 2.4degC increase), not FA input. All the zones have the same bias.

Cheers

JHW

Hi folks, 

(I feel a little bit retarded, seeing this discussion in Feb... but...)

approaching YBBN as QFA16 from KLAX also I noticed (now and some flights before) the change: 

Master is MM = 23, Target is TT = 25, Actual is AA = 25. 

After the long night flight (12:26 in the air, 45 minutes to go) pax shall get a fresh feeling now: 

Selecting a new setting with the master temperature knob MM = 22 changes the target temperature to TT = 22 and AA follows nicely. 

Strange that neither FCOM nor Kyle join the discussion. 

Is it Boeing or a human feature? 

... and only 20 minutes later TT = 23... 

Cough, cough, FCOM 2.20.5... gives all the info. 

Edited April 10, 20179 yr by 19AB67