NCDesign
Mechanical
- Nov 21, 2006
- 105
I'm not sure if this is the right forum, but this one gets lots of eyes so I'll give it a shot.
I just got surprised on a project with a 55 GPM per elevator sump pump requirement. This apparently originates from ANSI A17.1 Elevator code. I have 3 elevators sharing a pump so according to this I would need 165 GPM of sump pump capacity. This seems extremely excessive to me. The currently specified pump is rated at 65 GPM and when derated for hydraulic fluid could empty the sump (the sump and main elevator basin can contain the entire amount of hydraulic fluid so overflowing that is not a possiblity) in less than 10 minutes if there was a catastrophic hydraulic fluid event (all three elevators lost all of their hydraulic fluid at the same time). I would think that if all three elevators emptied their hydraulic fluid at the same time you would have greater concerns than whether or not the sump was emptied. I would think things like is the building still standing would be more important.
Furthermore it seems the ANSI requirement is geared more towards water build-up in the sump than hydraulic fluid. I don't have a large enough domestic water pipe in the building to supply 165 gpm of water and a good portion of the roof would have to leak into the elevator shaft to require this flow rate. On top of this per local code I have to provide exterior storage for whatever this pump pumps so it doesn't get into the sanitary or storm sewer. If there is a catastrophic water event (something that actually requires 165 GPM of flow) my storage tank will only contain it for about 3-1/2 minutes before it starts overflowing (although it will contain all the hydraulic fluid if it is just a hydraulic event.) So I am a bit puzzled. I am also a bit handicapped in that at this point I don't have the referenced elevator code.
I know this has been long winded but, does anyone here have any experience with this? Any other thoughts or words of wisdom? Right now I think this is ridiculous.
I just got surprised on a project with a 55 GPM per elevator sump pump requirement. This apparently originates from ANSI A17.1 Elevator code. I have 3 elevators sharing a pump so according to this I would need 165 GPM of sump pump capacity. This seems extremely excessive to me. The currently specified pump is rated at 65 GPM and when derated for hydraulic fluid could empty the sump (the sump and main elevator basin can contain the entire amount of hydraulic fluid so overflowing that is not a possiblity) in less than 10 minutes if there was a catastrophic hydraulic fluid event (all three elevators lost all of their hydraulic fluid at the same time). I would think that if all three elevators emptied their hydraulic fluid at the same time you would have greater concerns than whether or not the sump was emptied. I would think things like is the building still standing would be more important.
Furthermore it seems the ANSI requirement is geared more towards water build-up in the sump than hydraulic fluid. I don't have a large enough domestic water pipe in the building to supply 165 gpm of water and a good portion of the roof would have to leak into the elevator shaft to require this flow rate. On top of this per local code I have to provide exterior storage for whatever this pump pumps so it doesn't get into the sanitary or storm sewer. If there is a catastrophic water event (something that actually requires 165 GPM of flow) my storage tank will only contain it for about 3-1/2 minutes before it starts overflowing (although it will contain all the hydraulic fluid if it is just a hydraulic event.) So I am a bit puzzled. I am also a bit handicapped in that at this point I don't have the referenced elevator code.
I know this has been long winded but, does anyone here have any experience with this? Any other thoughts or words of wisdom? Right now I think this is ridiculous.