Water to Air cooler

manonboard

Hello my good craft masters!

I'm designing a device/system that im hoping will help cool a small work room I have. I press Tshirts n such and the heat makes the room an uncomfortable 27-30C+.

As my electricity bill is already quite high, I think a portable AC running for 5-8 hours will be expensive too.

Design theory: I am looking to build a water to Air Heat exchanger powered with a Fan. The water will be kept outside the house in a 240Liter Drum. I expect the temperature of this to stay low for autumn, winter, and spring.
Would this idea be feasible to cool 30C+ ambient room temp?

basically this: http://www.frozenboost.com/product_info.php?cPath=216&products_id=1034&osCsid=07445124688a150372b2c89bfc5c78a1

Except larger if possible, I have 4' of width room. and cheaper!

manonboard

I can find any Heat exchangers in Ireland so Shipping seems to be prohibitedily expensive.

Would a Car Radiator from a scrap yard suit this purpose? I dont know much about cars but I believe thier radiators simply have hot fluid passing through it and dissapates heat? Cold water fluid should have the opposite effect in a warm room i believe?

I can build a wooden box around it and attach a fan easily enough i believe.

Looking into how much energy a water pump + fan uses now, should be much less than Portable A/C which also requires venting.

manonboard

Power usage is tiny comparing to a Portable Air conditioner.

water pump + fan = 100 watts. A 9,000 BTU PAC will take 1,000watts!!

Thats ridiculous.

pumpkinsoup

manonboard wrote: »

Hello my good craft masters!

I'm designing a device/system that im hoping will help cool a small work room I have. I press Tshirts n such and the heat makes the room an uncomfortable 27-30C+.

As my electricity bill is already quite high, I think a portable AC running for 5-8 hours will be expensive too.

Design theory: I am looking to build a water to Air Heat exchanger powered with a Fan. The water will be kept outside the house in a 240Liter Drum. I expect the temperature of this to stay low for autumn, winter, and spring.
Would this idea be feasible to cool 30C+ ambient room temp?

basically this: http://www.frozenboost.com/product_info.php?cPath=216&products_id=1034&osCsid=07445124688a150372b2c89bfc5c78a1

Except larger if possible, I have 4' of width room. and cheaper!

I find it hard to believe that what appears to be a simple heat exchanger with a fan would cool your room adequately. I can't see how a 240 litre drum can extract the heat from a whole room perhaps a hundred times its size or more, particularly given ambient temperatures in Ireland. I expect that the efficiency of the unit would drop off quickly if the water heats up.

I know it's not what you asked but I would tackle the problem at source. I would look to see if I could get more energy efficient pressing equipment. For instance you can get irons now that stop heating up when not in use, which means less heat. The steam function also switches off which reduces the humidity, and humidity is probably main cause of discomfort in that environment. I would get a proper AC kit from a reputable manufacturer, if natural ventilation isn't an option. At least it would work. If you have people working with you, then AC is the only way to go.

manonboard wrote: »

Power usage is tiny comparing to a Portable Air conditioner.

water pump + fan = 100 watts. A 9,000 BTU PAC will take 1,000watts!!

Thats ridiculous.

Comparing energy use of the two solutions only makes sense if you know that they both can do the same job.

bbam

Could you not just open a window ??
Have you access to an outside wall ??

theTinker

pumpkinsoup wrote: »

Comparing energy use of the two solutions only makes sense if you know that they both can do the same job.

V good point

theTinker

pumpkinsoup wrote: »

Comparing energy use of the two solutions only makes sense if you know that they both can do the same job.

V good point!

refco

if you have acess to outside which i presume you have as your going to have a 240 litre drum why not just duct in fresh air no exchanger needed as outside air temp is for the most part below 16 degrees anyway

manonboard

pumpkinsoup wrote: »

I find it hard to believe that what appears to be a simple heat exchanger with a fan would cool your room adequately. I can't see how a 240 litre drum can extract the heat from a whole room perhaps a hundred times its size or more, particularly given ambient temperatures in Ireland. I expect that the efficiency of the unit would drop off quickly if the water heats up.

I know it's not what you asked but I would tackle the problem at source. I would look to see if I could get more energy efficient pressing equipment. For instance you can get irons now that stop heating up when not in use, which means less heat. The steam function also switches off which reduces the humidity, and humidity is probably main cause of discomfort in that environment. I would get a proper AC kit from a reputable manufacturer, if natural ventilation isn't an option. At least it would work. If you have people working with you, then AC is the only way to go.


Comparing energy use of the two solutions only makes sense if you know that they both can do the same job.

Thanks for the advice.
I had no idea a 240litre drum would be so insufficent, and that the ambient temperatures in ireland are not good enough. It just seems like so much water! and so cold out during the dark months! It gets freezing as you know.
I was hoping to take advantage of this usually forsaken state!

Ill have a further think about it and may go ahead or may cancel it. Thanks for the advice and feel free to contribute more if anything pops into your head.

@bbam. No windows in the basement and its a little below ground level so putting in a vent etc leads to issues when it rains etc! I have access to an outside wall yes.

manonboard

refco wrote: »

if you have acess to outside which i presume you have as your going to have a 240 litre drum why not just duct in fresh air no exchanger needed as outside air temp is for the most part below 16 degrees anyway

Im hoping to avoid making a 6" hole in the wall for the vent/duct.

A small 1/2" hole would much easier. Its solid wall.

cnocbui

solid what?

If it's just breeze block, you can fairly easily make a 6" hole for a vent by taking that 1\2" masonry bit and drilling a lot of holes through the wall in a 6" circle, then get a hammer and cold chisel and knock out the plug. You might want two vent holes. One on which you mount a bathroom extractor fan to vent the hot humid air to the outside and the other to allow cooler outside air to be drawn in to replace the exhausted air. If using a bathroom extractor fan you should only need a 100mm (4") hole.

I suspect such an arrangement would allow you to significantly lower the temperature.

refco

fair enough avoiding large core holes,next option i feel that if you installed an air to air heatpump designed for the room and equipment heatload the runing cost would be nearly as low as the water to air cooling you where working on
New a/c unit with inverter is A rated and when running will ramp down i have seen a 14kw unit running at less than 1 amp it was cooling a machine room at a holding temp of 20 degrees if the unit was turned off for 15 miutes room temp would rise to 29/30 degrees in that time restart a/c unit and it would start and runn at 8 amps for period of about 10 mins and start backing off from then back to using 1 amp electricty within the hour so running cost is very low

theTinker

cnocbui wrote: »

solid what?

If it's just breeze block, you can fairly easily make a 6" hole for a vent by taking that 1\2" masonry bit and drilling a lot of holes through the wall in a 6" circle, then get a hammer and cold chisel and knock out the plug. You might want two vent holes. One on which you mount a bathroom extractor fan to vent the hot humid air to the outside and the other to allow cooler outside air to be drawn in to replace the exhausted air. If using a bathroom extractor fan you should only need a 100mm (4") hole.

I suspect such an arrangement would allow you to significantly lower the temperature.

That sounds terrifying. I'd hate to put 2 large holes in my exterior wall. I dont mind knock dry wall around as i replace it when needed, but i'd really hate to put 2 6inch holes in my outside wall.

theTinker

refco wrote: »

fair enough avoiding large core holes,next option i feel that if you installed an air to air heatpump designed for the room and equipment heatload the runing cost would be nearly as low as the water to air cooling you where working on
New a/c unit with inverter is A rated and when running will ramp down i have seen a 14kw unit running at less than 1 amp it was cooling a machine room at a holding temp of 20 degrees if the unit was turned off for 15 miutes room temp would rise to 29/30 degrees in that time restart a/c unit and it would start and runn at 8 amps for period of about 10 mins and start backing off from then back to using 1 amp electricty within the hour so running cost is very low

Do these AC produce much noise in your experience? Is this a Mini split unit i've read about? A part on the outside, and a part on the inside?

That electric cost sounds alot better than i was expecting. Thanks for that! Im in fear that it will run full swing most of the time and cost me 100s in a bill.

cnocbui

theTinker wrote: »

That sounds terrifying. I'd hate to put 2 large holes in my exterior wall. I dont mind knock dry wall around as i replace it when needed, but i'd really hate to put 2 6inch holes in my outside wall.

You scare easy.

I put two 100mm holes through the walls of my previous house and one in the current one.

manonboard

I decided to go ahead with the Idea as i got the fan and radiator for practically nothing. No leaks
I have awater pump already so i might aswell. Im excited about the idea.

My next issue is powering the fan.

Ive been reading and a car fan seems to draw alot of amps as its 12V DC only.

Could anyone suggest a good way to power this from an AC. Is there adapters than output high amp?
Is it possible to just run it from a 12V battery source that plugs into a wall socket or something? Does that exist?

Thanks

bbam

manonboard wrote: »

I decided to go ahead with the Idea as i got the fan and radiator for practically nothing. No leaks
I have awater pump already so i might aswell. Im excited about the idea.

My next issue is powering the fan.

Ive been reading and a car fan seems to draw alot of amps as its 12V DC only.

Could anyone suggest a good way to power this from an AC. Is there adapters than output high amp?
Is it possible to just run it from a 12V battery source that plugs into a wall socket or something? Does that exist?

Thanks

I think something like this would be a beter alternative... A fan from a car radiator will be very noisy, not designed to run for long periods and you have the expence of buying a power supply to tun it...

http://www.argos.ie/static/Product/partNumber/4251817/Trail/searchtext%3EFAN.htm

bbam

I still think you're over engineering the whole problem.. :cool:

Go to a hire shop and hire a core bit to put a 4 or 6 inch honle in an outside wall.. Even having never done it before you'll run it through in about 20-30 minutes.. Cost of hiring the drill and bit will be about €30.
Get a grill for the outside, and a fan on the inside, will draw out alot of hot air in a few minutes... You could even hook up a thermostat to come on above a certain temperature...

If you don't want to do it yourself any half competant builder or handyman would do it in about 2 hours..

The system your building, while may be interesting to construct, will doubtfully work to any decent degree... You'll have spent enough €€'s to do a proper job anyway :rolleyes:

Sky King

I can't see this working - an a/c cooler would have a gas evaporation temperature of about -10C to provide heat x/c for cooling air to get the room down to about +18C - a temperature difference of 28C.

You're talking about doing this with water which will probably be around 12 to 15 C for most of the time and pumping it through something not designed for the pupose.

A far more sensible solution would be the A/C but if you are sold on this idea - then ditch the huge reservoir outside and have a second car radiator with a fan on it there.

You see, 240 kilos of water will have a very high thermal inertia and so you won't avail of the lower temperatures during the winter to the same extent.

if you had two car rads and a glycol solution to prevent freezing you would be able to get your coolant temp down a lot lower - making the system viable for a few months of the year at least.

Buf if you want my honest opinion - get AC. You're looking at maybe 0.75kW of power when it's running - that's one Euro per day provided the thing is going ding-dust (which it won't be) and you know it will work.

refco

im still of the opinion ac unit is the way to go also would say i have one fitted in hallway of my house and had it on heating all last winter considering the temperatures we suffered last winter it was hardly noticable on my esb bill