I don't have AC but my apartment lease covers unlimited water usage and the water is very cold. How can I best use this to cool my home?

Azuth@lemmy.today to No Stupid Questions@lemmy.world – 145 points –

I've searched around and mostly seen people create custom radiator builds attached to their water supply, but that's beyond my skill level and I'm not sure if linking it directly to the water supply via piping would violate the lease or not. Are there any solutions a bit more DIY that I could take advantage of?

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Almost no matter how you do it, it's going to be a horrible waste of good drinking water to try to extract cooling from the temperature of the water. If you are in a dry climate, make a DIY swamp cooler. Otherwise shell out for a small AC unit.

Also; using your free lease-included water for stuff like that, is probably the quickest way to no longer have water included in your lease...

So if

  • Using water this way is a waste of water
  • Using water this way will end the policy that permits this use case

Does that mean the fastest way to end the waste is to go ahead with this plan?

Only if that was your sole use of said water otherwise you're just going to pay more for all the water you'd normally use.

Get a kiddie pool, fill it, soak your feet in it

One of the best feelings in my life was returning to camp, consolidating coolers, and plunging my feet into the water in the leftover water in one of the coolers.

One time I took some instant release adderall and some MDMA and played Burnout Revenge on my friend’s playstation.

Wouldn't be too difficult to jerryrig a system which does that but because it's going to be a huge waste of water I feel morally obligated to not even give you any ideas. Invest in a split AC system instead. They make ones for windows as well.

AC is worse for the climate than wasting water

Is it though?

Depending on where you live yeah

So no. If portions of region A are below region B, then region A is not above region B.

Youre not necessarily wasting any water. Any water that goes down the drain just gets filtered and recirculated. Even if it wasn't filtered and made it directly to the river, evaporation would still ensure it returns to the cycle.

Not as far as the efficiency of filtering water vs an AC... well. You'll need someone significantly smarter than I to tell you that

The wasting of water refers to water that is available for use by people. Water that’s been treated and is ready to go.

By your definition “wasting water” is impossible, since it all stays on Earth and will get filtered eventually.

That was what I was going for :p. Had hoped an engineer might come in and tell us the efficiency of either or both.

Is there a reason why you can't get an air conditioner? There's tons of valid reasons why it wouldn't be an option, I'm just wondering what your situation is. Because nothing is ever gonna work anywhere close to as good as an air conditioner. If you can afford even the smallest air conditioner then it'll beat every single diy method in most situations

As a kid I used tubes, a box fan, a cooler, and bucket with a siphon to cool me down.

You could easily set that up with just the water from a sink and some hardware store parts.

Search for 'diy fan cooling tub copper coils' as a start.

As an example: Homemade AC - The "Copper Coil" Air Cooler! - (Simple "Box Fan ...

Copper coils have the best thermal efficiency, but plastic tubing would also work.

Get an actual radiator instead of making coils and attach a box fan to it. It's something I was always going to do but never got around to.

Also give consideration to saving at least some of the water to use as "gray water". If you're not familiar with that, it means water you can use for many things but not for eating or drinking.

Feasible if you found one at a junk yard, but copper tubing is $20-30 and some fittings makes a tubing idea sub-$100 probably. An AC is about $300, a new radiator without fittings starts at $70 and are built for cars not box fans so it might be more challenging to get to work.

With that being said, environmental, energy, and other contextual concerns might out weigh the cost. A mini-split heat pump is probably the most sane thing to actually install, but that's a big ask.

You don't need copper tubing, any tubing that'll hold water will work. There aren't going to be high temperatures or pressures. The supply won't be able to go full blast with poly and hose clamps but it wouldn't need to. I had a whole plan for this in my head then moved somewhere I didn't need it and never made it happen.

As for a mini spit, that's the easiest option if the central is shot, if the layout isn't complicated. But the place isn't owned by OP so it's probably a non starter. They don't even want to fix what's there it sounds like.

Get an actual radiator instead of making coils and attach a box fan to it.

Or, get an AC unit at that point.

Start a car detailing business. Use the water to wash the cars.

Use the money from new, low-overhead business to do anything you want.

  1. Find a pair of vehicle radiators that are as close to a box fan in size as possible.
  2. Zip tie them to either side of the box fan. As the fan blows: it will draw air in through the “second radiator” and blow it out through the “first radiator”.
  3. Hook the out of the first radiator to the in of the second using flexible hoses. Cheap garden hoses might even fit.
  4. Hook other hoses to the in of the first radiator and the out of the second.
  5. Run water on through the first radiator, out of the second. This makes the most efficient heat transfer possible.

This is exactly what I was going to suggest. Use the water to cool the radiators, and use fans to push hot air through the cool radiators, cooling the air in the process.

This is basically what AC does on a much larger scale. It uses refrigerants, a compressor, and some basic physics to cool the radiators, but it’s still the same basic concept.

I don't think a box fan could cool one entire 20x20in automotive radiator, let alone two.

fan -> plenum -> radiator would probably work best. The plenum only needs to be a few inches long, it's just to direct the entire square of the fan over the entire square of the radiator. Cardboard and caulk would work.

It's a low efficiency heat exchanger.

If the actual problem is that you yourself are too hot, cool yourself instead. A trick I've picked up working in kitchens, where it's very fucking hot indeed, is to wet your nape and forearms regularly. You can wear a wet hat too. Doesn't really take advantage of the unlimited water but it gets you there.

Gut an AC from the dump. Replace the condenser with a tube in tube heat exchanger, using your cold water as a heat sink. Brazed plate HX if you're feeling rich. Replace the cap tube with a TXV for better load tracking. Recharge with R290.

T Sure this is even further beyond your skill level but is the best possible way to use a source of cold to chill your apartment. You can locate it anywhere convenient, not just by the window. You could likely get a COP over 5 and be discharging the water in a fairly modest stream at around 30-40C.

Depending on you humidity, you could look into building a swamp-cooler. Sounds weird but works pretty great.

Could you get a fountain?
Specially if it spreads the water like rain, it'll help cool the air around, you'd just have to change the water every so often.

If where you live is not very humid you could investigate into swamp coolers.

I don't know how big your apartment is but why not a window unit. It's probably the most efficient way to cook your apartment down short of redesigning the building.

These are very expensive to run. They can add upwards of $200 to your electric bill.

It's either that or maintain a swamp cooler that won't work on humid days and can cause respiratory infection if not cleaned properly. A renters options are very limited and a window unit is a pretty good compromise if you don't want to loose a deposit.

If you want to sit in a sweltering room during a 100° day, no one is stopping you. I've heard it's a pretty typical thing for Europeans anyway. I'm not judging, the guy wants to cool the room down.

OP would probably be better suited with a portable AC. Most apartments I know of ban window units because they can fall and hit people if not installed properly.

When getting a portable AC, get one with two hoses as they're much more efficient since they aren't blowing cooled air outside (and sucking hot air in from every gap in the exterior walls.

Yeah, whatever is reasonable and within the terms of your lease is usually the best bet.

Depends on your electricity rates. Ours is around $0.12/KWh and doesn't even cost 1/4 of that.

Depends on the area too. I live in Texas and can tell you from my personal experience that at .14/kw it increased my bill by about $200

Maybe you have a bad AC. I've been running ours nearly daily and our electricity bill has gone from $120 to $140

Just get a window AC if you have the right type of windows. Otherwise, a dual hose portable heat pump from costco or other reputable source.

You could try and make a DIY swamp cooler? There's lots of instructions online for how to make them, and basically the only consumable is water. The only caveat is that they work by drawing hot air in from an open window to evaporate water, so it's not very effective in high humidity or low temperatures.

Spray water in front of a fan. Way faster than forcing heat exchange through air to metal.

The reason it works on Winter is that the temperature difference is about 50C or more. On a hot 35C day it would mean the radiator is at most at -15C.. And that's why you'll prefer to stand in front of the fridge that has 6C than a radiator that may run at best 15C water inside.

Just run your shower with cold water. Open a window on the otherwise of the house and get a fan to blow air from the bathroom to the open window.

As the water turns from liquid to gas it absorbs heat. As long as it doesn’t get too humid it should feel cool.

Dehumidifier.

little realized fact that dehumidifiers produce heat

If you say so. The air just feels a lot more cool and crisp in my apartment when I have my dehumidifier on. Of course I live in a swamp so without it if feels like I swimming through stank ass when I walk somewhere.

I'm not doubting the science behind your statement. I just prefer feeling like I'm not being sous vide, so I'll stick to a dry heat in my apartment.

A dehumidifier would return heat to the room. Best you can do with swamp cooling is draw the humid air out.

I've done this!

Turn the shower on just high enough to get a good mist going then put a box fan on high as close as possible pointing out of the bathroom.

Ice machine + box fan

Put ice in a container with a large surface area, aim the fan at it. Empty the container when fully melted. Put ice in all your drinks