I have several Climate Master TTV, TTH, and TTS units manufactured in 2007. All have Climadry (the Original version not the II). Our building uses a closed loop condenser water system. We only use air-conditioning (no heating) and our return air temperature is usually around 74 degrees F. Incoming water temperature is always between 87-90 degrees F. We run the cooling all year long but Climadry will probably only be required a few months per year. Can these units be used on our system which has NO antifreeze in the condenser water? Or will we be at risk from the reheat coil freezing and rupturing? And if we cannot use them on our system with NO antifreeze, is there a way to disable Climadry so we won’t use it and it is not at risk of rupturing? Maybe somehow empty the reheat coil of water and then remove power from the three way valve and Climadry pump and simply not hook up a dehumidistat?

Count the work, please. The heat running hours at an output vs chilling needed to maintain operations, and not that they will be equal, but just what are the "heating tons" to cooling tons.

You will be able to determine a rate of absorbed "chilling" BTUh, for the unit that may be concerned going "to freeze".
Techs a CM are great folks to talk with.

In one typical condition:
a ratio (for starters) of 4 units heat (read label on the compressor inside) for each 3 units of cooling is simple to begin with figuring freeze-up.
some start with 5:4, Ht:C, respectively.

open loops entering fluid 50, typically do not want to see 38 leaving fluid temps

higher speed circulation say 4.1/2 gpm per COMPRESSOR-LABEL ton can leave you with allowing to safely (check stopping moment freeze-up)
down to 37 leaving -,
A degree lower (only to 36 leaving) , and 5 gpm per ton or more, all pipes engineered good to go...
and you may have to be considering time-delayed circulation after compressor(s) are "off" to 'relax' back to refrigerant above freezing, as a control system.

...

I would check your manual or with climatemaster, but I can't see why you couldn't run climadry with your app.
If you want to disable it, it is as easy as not wiring the control side.

Q's:
1) Can these units be used on our system which has NO antifreeze in the condenser water?

2) Or will we be at risk from the reheat coil freezing and rupturing?

 3) And if we cannot use them on our system with NO antifreeze, is there a way to disable Climadry so we won’t use it and it is not at risk of rupturing?

 4) Maybe somehow empty the reheat coil of water and then remove power from the three way valve and Climadry pump and simply not hook up a dehumidistat?

His q's are as I may understand:

1) Workable without antifreeze ?
YES - IF about using controlled minimum temperature of leaving water which is in all cases in a public posting-  to be found at above 38F/LvWtr at 3-to- 3.3 gpm per ton of compressors[cT] (read label inside these units for real tonnage). Some OEM techs at 2 gpm/cT LW allow "above 39F".

2) see 1)

3) YES. and CM techs will help you find the wiring to controls that can be disabled. and 4) See 3).

call Joe  (his advertised website is in his post)   he really is very patient and considerate and may be of further help and tells you when he does not know something

Andrew, here is a little more info on Climadry. My system (TTV026) was mfg in 2011, so is more recent. According to CM, there indeed was a concern about freezing the Climadry coil under certain circumstances. Their documentation does say that antifreeze protection is recommended for units mfg before April of 2010. From my notes on a conversation with a CM tech guy, he says they have changed the U-bends at the ends of the coils, for adding mechanical strength, rather than provide a bigger cabinet to give more physical separation between the Climadry coil and the evaporator (in cooling mode) coil just upstream. The freeze problem was seen when air flow is too restricted, as by a badly clogged filter, and the air temperature more closely approached the evaporator coil temperature. The moisture could freeze and ultimately bridge the gap to the Climadry coil. It is the Climadry coil that could possibly fail, not the COAX exchanger. The freeze problem won't occur in heating mode, as the upstream coil (then the condenser) is warming the air.

In your case, in cooling mode the air from the evaporator coil still will have to be cooled to perhaps 50 F or so to remove moisture adeaquately, regardless of ground loop water being at 87-90 degrees. It just won't take as much water flow looped back through the Climadry coil to rewarm the air to room temperature. I suspect that most of the time there will be a need for cooling and dehumidification simultaneously [edit: or cooling alone]. Then there will be incoming signals on both Y1 and at the H connection on the DXM control board. In this case the little pump for looping warmed water back through the Climadry coil is not turned on at all and no water flows through that coil, [edit:] although the coil still is full of water. It is this condition that could result in freezing under conditions of restricted air flow. The Climadry loop pump is turned on only for "reheat mode," determined by input to connection "H" but not to "Y1," and the circulation of warmed water will prevent freezing. [end edit]

I wouldn't think you would have any freezing problem, as long as you keep the filters from getting badly clogged. Regular maintenance ought to suffice. Otherwise it probably would take just a minor bit of plumbing work to drain and isolate the Climadry coil from the rest of the system. Disabling the system, control-wise, should be a simple matter of not connecting anything to the H input on the board. This presumes that your board is some earlier version of the DXM board; I don't see any input for humidity control on the CXM board diagram.

In any case, as Joe indicated, talk to the CM tech people. I found them easy enough to get to and talk with.

Andrew.
There are also simple sensor @ 35F alarms at kitchen-wares and appliance stores, to radio shacks, also which beep aloud for the warning before a freezing-air or water-pipe condition may occur. That sensor is about 1/8" in diameter.