cooling an elevator cab
cooling an elevator cab
(OP)
I need help with cooling an elevator cab. I have 30 elevators with 1400 watts of halogen cab lighting generating a lot of heat. can this be dissipated through ventilation, if so how much cfm of air movement do I need. Or will I need some type of air conditioning unit. any calculation would be apreciated. The cab dim. are 5'x6' with 9 ' ceilings





RE: cooling an elevator cab
RE: cooling an elevator cab
RE: cooling an elevator cab
My condo's elevators probably have less than 120 W of incandescent lighting.
TTFN
RE: cooling an elevator cab
RE: cooling an elevator cab
Next I would install occupancy sensors in each cab to turn the lights off when empty to reduce the heat load.
It's possible with ventilation only, but it depends on the temperature of the air available for ventilation (typically from the elevator shaft).
Short-form equation is:
q = 1.07 x cfm x (Ti - To)
where:
q = heat load in BTH/hr (1,400 watts ~= 4800 BTU/hr)
cfm is the cubic feet of air at temperature To that you need.
Ti is the temperature in the cab you want to maintain.
To is the temperature of the air you have available for ventilation.
RE: cooling an elevator cab
1.07 x 2250 = 2407 x 2 = 4815 btu/h
we do have timers to shut off the lights after 1 minute of no demand. the fans stay running, although they probably do not move the amount of air necessary
RE: cooling an elevator cab
TTFN
RE: cooling an elevator cab
Likely not comfortable. You're gonna need colder air.
Why is there so much lighting power in these elevators?
RE: cooling an elevator cab
RE: cooling an elevator cab
Another issue that crops up here is that airflow provided for the lights will cause faster cooling of the lights when they are turned off. The high thermal gradient may cause premature failure of the filaments, since the vaporized metal cycle will shut off prematurely because the cooler than usual glass will cause condensation of the metal onto the glass, rather than back on the filament.
TTFN
RE: cooling an elevator cab