Here here. You should only be charging for billable time or related research, etc. Unbillable time would be a business decision and it doesn't sound like yours to make.
Killing time should be on your time.
Consider winter operation and operation under low loads. A three way bypass valve below the roof level may help with this.
The main piping should be insulated throughout the building if CW used for free cooling in the winter.
If your sweet energy recovery gear is really working nice...document the energy consumption. take a look at the loads...are there opportunities to conserve? You may save "less" energy with your fancy gear if you reduce the load, but you'll be using less energy overall, which has gotta look good...
If you don't have pressure independent flow control valves you may be better off with the sensor "2/3" of the way down the main run. Differential pressure setpoint should be determined based on full flow and 100% system demand. I don't think you want to control the system based on any one...
Careful applying the VRF to tele/data closets. These units don't have the same low ambient operation as their smaller (1 indoor :1 outdoor) cousins...VRF won't cool during cold winters.
I would suggest developing a relationship with a good mechancial contractor. They can use your engineering insight and you can use their industry experience.
Definately agree with mauricestoker...in a refrigerated room, humidity is determined by the coil TD, the match between the nominal capacity of the evap and the capacity of the condensing unit. Higher TD, colder coil, more frost on the coil, and out the drain during defrost. Definately make...
The "drop" solenoid prevents refrigerant migration during the off cycle. I believe the manufacturer is concerned with the total amount of refrigerant in the system once you get into longer pipe runs. Liquid refrigerant will migrate to the coldest part of the system, then flood back to the...