Domestic closed loop evaporative cooling

[Uncle Fester]

Does anybody know if there are closed loop evaporative coolers for home use commercially available or do I have to invent/design/build one?


I am talking about an 'swampie' system that does not increase the humidity of the air in your house by using a thermal transfer system.


Also I noted in another thread that swampies are installed on rooftops, exposed to the sun. I would have thought it would be better to keep them cool, i.e. on a south side shaded wall but maybe the heat from the sun makes them evaporate quicker and increase efficiency?
Can anybody from the trade or experience explain please?

[lsemmens]

I am neither fridgie, nor expert, but would not a "closed loop" system just increase humidity as swampies cool by evaporation, thus, increasing humidity. In a humid environment they become less efficient, so, by working in a closed loop, surely they would become less efficient. I do agree with the rationale that shade might make a difference, but have little experience to either confirm or deny that. Over the last few days with our ducted swampie running, there was an approx 16deg difference between inside and outside i.e 44C on the verandah in the shade to 28C in the kitchen.

[ol' boy]

Or you could build a Swampie, in a Swampie and have a 2 Stage Cooling system

Dry Bulb, Wet Bulb, Dew Point etc.... There is only so much you can achieve from evaporative cooling on a given day, physics has its ceiling, and is where mechanical refrigeration takes over is you require further cooling.
Swampies are all about air flow, the faster the moving air at the head unit the better, hence on the roof is probably better than under your house

[ssrattus]

There is a system that uses thermal transfer so the air is cooled but no added humidity. See We are looking into it for our new building at work.

[Uncle Fester]

There is a system that uses thermal transfer so the air is cooled but no added humidity. See We are looking into it for our new building at work.

Yes, that would be what I am talking about but it does not seem to be for domestic use and probably way out of my budget including transport/import issues...but now I know about the Maisotsenko Cycle

Isemmens, that is fantastic performance. Do you know what humidity range were you experiencing (outside and in)?

Ocean, from some evaporation experiments I found having it in the sun is very inefficient.

My experiments showed a drop of the aluminium I was cooling from 30C to 24C at 60% humidity outside in the shady south, not great but maybe still somewhat usable.

[ol' boy]

Yes nomeat, there are covers you can get for some Evaps, to protect them from direct sunlight.

[beer4life]

We've been down this track before.

The criteria for efficiency is humidity, the lower ambient humidity, the better.
Notoriously inefficient around the coastal regions, while quite acceptable for the outback.

This is a fact of Physics and not open to conjecture or hearsay.

[LeroyPatrol]

There is a system that uses thermal transfer so the air is cooled but no added humidity. See We are looking into it for our new building at work.

I know someone that cycles their air through the ground for their house cooling!

Leroy

[lsemmens]

Sorry, nomeat, didn't check RH when I looked at the thermometers. I could have done so as I have a multimeter that does Temp and RH. I was using it to test some dash lights whilst I had my car apart (fixing blower fault, so had the dash stripped) and, as it was more than one or two, I took them all inside and sat down with a brew to "do the deed" The aircond was on at the time and RH in the lounge room was around 39%, not sure what it was outside, didn't check. I live inland so humidity is not a huge problem.

[Softek2]

I understand this is a fairly old thread but this info might be of some assistance. I use a similar system to the collorado which has been in use since 1993. we are about 100k west of the coast. Except for the electronics ie fan speed control & reverse direction of the fan everything is as it was fitted. In 2001 the control circuitry blew up and as usual the (WA) company had gone bust. The number turned out to be an X employee who painstakingly explained how to get the head to work at full speed only. I fitted some X10 switching and replaced the circulating pump when it rusted away. We give the pads a clean every year and no other maintenance. The air in is divided in half with the waste air going in to the ceiling cavity and blown out the end of (my gun barrel house). The remaining air is passed over the cool chamber through another set of pads through a dropper and out to 300mm ducts (8). At most times the house is at least 15 deg cooler than the ambient. There are some (about 5) days a year when the cooler is only a few degrees cooler than outside BUT it is still comfortable inside. The blower fan & pump motor draw a modest 700W. Also to be noted is you do need air flow to outside to keep the house from becoming a suna, however, a bit of playing around with open doors & windows will ensure maximum cooling in the most required areas about the house. We exhaust the air through a shade cloth out door living area for added comfort.
Hope you find this useful.
Regards,

[gordon_s1942]

We've been down this track before.

The criteria for efficiency is humidity, the lower ambient humidity, the better.
Notoriously inefficient around the coastal regions, while quite acceptable for the outback.

This is a fact of Physics and not open to conjecture or hearsay.

As B4Life says, this depends entirely on where you live for the most suitable form of cooling, anywhere along the coast that stays under a 1000 metres or where theres no land rise, 50 kms inland you can use most types of Air Conditioning but once you climb over the 1000 metres or get further inland , then evaporative coolers come into their own.
Because most Air Conditions inherently dehumidify the air by their design, it can cause some to experience a dry throat or even respiratory problems so moisture may need to be added.
A neighbour has a roof mounted evaporative cooler which works brilliantly but when its going, most of the doors swell up and wont close because its adding moisture into the air.

[Thomas Ennis]

Swamp coolers are loosing popularity in the US. The never work well in humidity, and they tend to use a bunch of water. The state I live in rests in the middle of the desert. Local policy makers are considering passing laws to ban swamp coolers because of the water usage. They are offering a credit for people switching to refrigerate air installation.

[lsemmens]

I was researching water usage of our swampie and came across . Makes for some interesting reading.

[Softek2]

Thanks Isemmens, the article was a good read and answered some questions on efficiency of the units. Over the past few years my unit seems to be a bit lazy (although the temp logs dispute that). The pads are now 24 years old and the dump valve failed in 1994 without being able to find an equivalent so was disabled. We are on tank water so salt & dust until recently probably didn't have a large bearing on the unit capacity, however, over the past 5 or so years we are now neighbor to a coal mine (less than 1000mtr to the pit) which will change things considerably with the advent of more activity.
Thanks again,
Regards,