With all due respect this project is going to cost you a lot of money in installation and operations unless you get a little beter informed. Water treatment for chillers has nothing to do with a water treatment plant. As water evaporates it leaves minerals behind, a conductivity meter will monitor that and automatically bleed off the minerals, biocides for allgae, and various other chemicals that keep the minerals from collecting on the heat transfer surfaces are part of what I am calling water treatment.
Originally Posted by hotNcold59
This is a new system so your pump arrangement and piping arrangement and the potential use for VSD's on the pumps can have a huge impact on your plants efficiency. You could have several small chillers in decoupled loops, each with it's own chilled water pump. With modern automation there is so much that can be done to make aplant efficient. Your focus shoud be total plant efficiency, the whoe plant not one component of it.
I would suggest you get a professional engineer or at least search the ASHRAE website as well as the department of energy website for chiller plant design tools. Your leaving a ton of money on the table focusing on chiller manufacturers sales data.
Both manufacturers offer VFD options for their chillers, one thing that they seem to overlook while "selling" the VFD option is that in order for the VFD chiller to work to its full potential you need to have some condenser relief, in other words you need colder than the design of 85 degree condenser water.
I have seen several jobs that were sold with VFDs that were supposed to save a bunch of energy, but the savings went out the window when they had run the towers balls out all the time.
What state are you in, does the air cooled run in the winter and the water cooled in the summer if so I dont think the pump energy savings will be that much between the York and the Trane. The energy savings of pumping 2 gpm versus 3 gpm are about $ 2200 assuming the pump runs 24/7 if you shut it down for the winter obviously your savings decrease.
Sounds like you have a couple of sales engineers that are giving you a lot of options that you may or may not need. Have they given you any energy savings reports based on VFD chiller versus non VFD chiller, with any proposed payback. How many hours is the air cooled going to run a year versus the water cooled?
Who is laying out the piping design, is it a decoupled loop or something else?
If you dont stand behind our troops, please feel free...........to stand in front of them.
If you are thinking about a 700 ton water cooled then you are also thinking 123 vs 134a since Trane only makes a 123 machine in that size. I think the Trane machine in that tonnage range is about the best thing out there. It will take higher condenser water temps before it surges and with the low pressure refrigerant it is also very easy to service. You don't have to pull the charge to do most repairs to the machine. Your aircooled machine could be either manufacturer but I have to say I like the CH530 panel on the Trane. But the York is very nice as well. I have experienced more failures with York components on these machines though. Sensors, transducers, boards, fan motors and the like.
Google 123 refrigerant. Yea, it really sounds like you need an engineered solution as opposed to guessing. In putting together a comprehensive package for a new system there can be many variables. What type of system are you using? single or variable speed pumping? any radiant cooling panels or underfloor? both affect supply water temps. tow or three way valves at emitters? physical size restrctions, noise restrictions? cooling tower location?