This could already be a product, avaliable to buy.

Being an HVAC nerd I came up with idea for a compact & modular split A/C system that can recirculates plain old water on the cold side heat transfer loop, as opposed to using refrigerant. The hot side loop would be like the one on a Window A/C or split A/C, using a regular refridgeration cycle. The cold side loop would be much like a car radiator, recirculating water to transfer heat. The unit would have water recirculation pump built in with safety features like dry line shut off, leak indicator, etc. There could be fitting for vinyl tubing, or garden hoses; depending on efficiency and scale of this split A/C. The split A/C recirculates plain water or water with antifreeze in it, There can be a drain valve for the former for when the lines start to freeze.

The cooled space could be 100 feet away from the unit and still be relatively efficient depending on whether the water hoses/tubes are insulated and/or out of the sun. The unit itself is portable and modular, a little smaller than an average window A/C of same BTU. Can be fitted like a rolling suitcase or backpack.

A tinkerer would have the option to build their own cold side exchanger lowering the cost of Split A/C, needing no HVAC cetifications since they are working with water lines and not refrigerant lines. Condensate handling is up the the user, with manufactured options to handle the A/C condedate.

There is something like this already, factories and warehouses have industial chillers that recirculate water instead of refrigerant. They do not have small scale of these at a price near the cost of a window A/C. Central A/Cs could be made like this, and cheaper because they do not need to run refridgerant to the heat exchangers . Tiny A/C less than 5000 BTUs could be made like for many situations and setups. RVs, temporary enviroments like construction sites, passenger cars & trucks with non-operational built in A/C, people living in strict apartment complexes, situations where the A/C unit needs to be hidden away etc.

Cheaper, flexible, modular, user serviceable, portable split A/C; what more can we ask for?
-- Dignium, Dec 13 2015

What's the difference between what you're trying to describe and a split A/C like the ones you see in houses and stuff.
-- FlyingToaster, Dec 13 2015


I'm the new M.C.

I'm the Digni D

I'm the industrial chiller-like split AC
-- bungston, Dec 13 2015


Dig I want to understand this better but it might need a picture. Can you illustrate standard AC and how yours differs, then link it up?
-- bungston, Dec 15 2015


//There is something like this already, I hear factories and warehouses have industrial chillers//

Yes They do.

Warehouses with several "air handling units" control the temperature (just a air filter, heat exchanger and blower). Heat and AC. The air conditioning is accomplished with evaporative cooling towers outside. This system is far less efficient than using refrigerant. But the trade off is that the system using just water is safer and simper than running refrigerant lines all over a huge building. These units are prone to leaks and a refrigerant leak would be much worse than a water leak.

So that's why you don't see them small scale.
-- evilpenguin, Dec 15 2015


It seems to me that what [Digniuum] is looking for is a do- it-yourself friendly system where the external heat exchange medium circuits are water or antifreeze, so anyone who can do a little plumbing can build the system how they want.

I believe the terminology used in the idea description is using is technically incorrect. By definition a "split" system has compressor and condenser outside and the evaporator inside. Therefore the fluid going between those must be a refrigerant, not water/antifreeze. But I think what is desired here is a system packaged like a split system.

It seems to me the place to look would be a system designed for geothermal and hydronic. That will find you a water to water heat pump. A quick search found several providers. Unfortunately there are no prices listed. They seem to be in the 20,000+ BTU/hr range (whole house systems). I'm guessing it may be hard for a non-professional to acquire on of these. If you could, they would probably be in the multi-thousand dollar price range.

Something else to consider for playing with might be a GeoSpring hot water heater from Lowes. That has water on the hot side that can be piped where you please, but it just has air on the cold side. You get a fairly small compressor for the money since you're buying a water tank as well.

It does seem strange how much a whole house heat pumps cost compared to the heat pump capability you get in a window A/C unit.
-- scad mientist, Dec 15 2015


"Dig I want to understand this better but it might need a picture. Can you illustrate standard AC and how yours differs, then link it up?" Is it possible to post pictures on HalfBakery? " It seems to me that what [Digniuum] is looking for is a do- it-yourself friendly system where the external heat exchange medium circuits are water or antifreeze, so anyone who can do a little plumbing can build the system how they want."

A fully DIY friendly A/C unit that is modular with refridgerant system adapted from a Window A/C. The refridgerant on the the cold side loop is intermingled with a water/antifreeze recirculation loop, fully customizable by the user. The water antifreeze loop can theoretically be a mile long. Since the user is not dealing with refridgerant but water/antifreeze mix, it's a cheap and reconfigurable "split" A/C system.

One can achieve the same or close effienciency as a Window A/C with the flexablilty of a Portable A/C. This puts custom A/C systems in reach of the 99%. The A/C unit could be manufactured on the same production line as the mass produced window A/C units and cost about the same for the consumer.
-- Dignium, Dec 26 2015



random, halfbakery