Elevator¦s Machine Room Ventilation 1

[galvic]

Hello.

We are designing ventilation, 10 AC/h, in our elevators machine room. The reccomended choice would be use air conditioning, but we have some problems to conditioning two machines rooms, because they´ll be located in underground galleries. The air inside this galleries will be at 38°C DB.

The question is if modern microprocessors controls could work under this conditions only with ventilation. Could we ask for controls that can resist?.

Thak you.

 

[rbulsara]

You will have bigger problems and blames to share if you choose not to air condition it, imho.

Do not foget to dehumidify too , to eliminate condensation.

 

[remp]

You have 2 choices.

No. 1 - air-condition the space to room temperature approx 24 deg C - use a split a/c system if need be. Local codes may require minimum ventilation in a motor room. You will have to find out the heat emitted form the motors to size your a/c unit

No. 2 - Ventilate the room. You will need to know how much heat is emitted form the motors - the supply air temperature ( max summer outside air temp, since you are ventilating it with outdoor air) the room temp ( max acceptable room temperature, 28-30 may be acceptable, again look at local codes). use the Q=m.c.deltaT formula to get your air flow rate (m)

Dont just use 10ac/hr - this amy be too much unless local codes reuqire a minimum of 10ac/hr. 10 ac/hr may also be too little.

If you live in Australia, they have a standard specificly for this regarding a/c and ventilation temperature requirement etc..

Good luck

 

[galvic]

Thank you very much.

I think that the split A/C system will be the right choice. But I don´t know if is recommended to install the condenser unit in an underground gallery, I have to ask the A/C equipment manufacturer if there is no problem with this alternative.

 

[ChasBean1]

Billyg, well-put explanation and nice post.

In US (MA) code requires elevator machine rooms to be ventilated (not just conditioned). Provisions allow a ventilation substitute of machine room connection via ductwork without a fan (there are requirements regarding duct pitch) to the associated hoistway. The piston effect of the elevator continually changes the air in the machine room. I would think the purpose would be dissipation of gaseous hydraulic emission. Think of it - a hydraulic system in a conditioned but not ventilated space could evolve into LEL and O2 depletion issues...

If it's all electric, I believe the code still applies but maybe for nostalgic reasons moreso than the code's original intent...