Cold air complaints
Cold air complaints
(OP)
Hi all,
I am getting a lot of complaints about recently commissioned Centralised AHU system serving an open plan office.
There are a number of wall temperature sensors in the area and they all read the desired values (between 20.3 C & 21.8 C to a set point of 21 C). The supply air temperature is 15 C but even at the supply air temperature of 18 C the complaints were still coming through.
The ceiling in the office steps up by 1m half way through and only the people in the area with the higher ceiling complained.
As the AHU operates in cooling mode I would expect the people under the lower ceiling to complain more– if there are any problems. What’s happening is totally opposite.
The velocities through the ceiling diffusers are reasonable low ( less than 2.5) but in any case are the same across the whole office.
Can the 'coanda' effect speed the air up along the higher walls causing more draught?
The humidity is not controlled nor there is a need for that but it’s generally high.
Has anybody got similar experience?
Regards,
I am getting a lot of complaints about recently commissioned Centralised AHU system serving an open plan office.
There are a number of wall temperature sensors in the area and they all read the desired values (between 20.3 C & 21.8 C to a set point of 21 C). The supply air temperature is 15 C but even at the supply air temperature of 18 C the complaints were still coming through.
The ceiling in the office steps up by 1m half way through and only the people in the area with the higher ceiling complained.
As the AHU operates in cooling mode I would expect the people under the lower ceiling to complain more– if there are any problems. What’s happening is totally opposite.
The velocities through the ceiling diffusers are reasonable low ( less than 2.5) but in any case are the same across the whole office.
Can the 'coanda' effect speed the air up along the higher walls causing more draught?
The humidity is not controlled nor there is a need for that but it’s generally high.
Has anybody got similar experience?
Regards,





RE: Cold air complaints
Also, 21.8 seems to be low per ASHRAE. ASHRAE recommends about 23.9C. Have they tried increasing the space temperature setpoint?
RE: Cold air complaints
RE: Cold air complaints
Accutherm thermostatically controlled diffusers may help, but probably not.
RE: Cold air complaints
RE: Cold air complaints
i am talking about thermostat setting. if you count variations of 1-2 C inevitable for open spaces, your will find that with your 20 C measured it could be found down to 18 C and some spots, and everyone will complain in such circumstances.
raising temperature setting should be first solution to attempt with. if someone would complain for feeling too hot afterwards, you should check local heat sources. you would not want freezer atmosphere in open office only because two seats are too close to concentrated location of hubs/copiers etc.
this question seemingly has to be tied to office space organisation.
RE: Cold air complaints
The hunidity around here is ususally high which doesn't help either.
Regards
RE: Cold air complaints
But one thing that has been useful with complaints from people in an otherwise well balanced office.
Is a dummy thermostat closest to the loudest complainants.
B.E.
You are judged not by what you know, but by what you can do.
RE: Cold air complaints
RE: Cold air complaints
This sounds like a classic case of over sized DX.
RE: Cold air complaints
RE: Cold air complaints