Car Misting System (cheap Air Conditioning Alternative) - V0.1 Manual Pump

The Problem:

It was a hot summers day and I was cruising down the highway (window closed for the noise) and thought to myself, “I really need aircon... or something.” Air conditioning, while lovely, is both expensive and far too ordinary for my extra-ordinary car. So the something I decided on is a misting system. I purchased the components for a minimum viable product over the weekend.

Step 1: Gather Components

I live in South Africa. So to get this done by the end of the weekend, I had to settle on some things. Hence this being V0.1. But it's probably the cheapest way for you to get it done anyway.

First you will need some sort of pressure sprayer. Something like this

Next you will need to purchase a misting system. I purchased something very similar to this

Washers that your nozzles can fit through, but prevent the larger part of the nozzle from going through.

Tube clamps. Something like this

But if you have the luxury of finding a shop that can sell you the nozzles and tubing separately, then rather do that. Not only will it be cheaper, but you won't have to struggle with cutting the old tube out (which was more of a mission than you would expect). You may even be able to get better nozzles. There are anti drip nozzles (which would be lovely), and ones with finer holes - note that you will need higher pressure to use these so do so at your disgression) so you are misted rather than sprayed (the difference between being wet and being cooled). As I said, this is my prototype version and when I can get the components I really want, I'll make a better one.

In my design I found washers in my garage that happened to be the perfect size for my nozzles. So if you want to achieve a similar finish to mine, I recommend you do that.

Step 2: Dashboard Removal

My car is a classic mini. The dashboard is anything but complex. If you want to do this to your car, I think I can assume you don't really care about a little destructive remodelling. By destructive, I mean irreversible. If I wanted to, I could just remove the vinyl from my dashboard and replace it with another without holes, so nothing is reversible.

Anyway, remove your dashboard however it is supposed to be removed on your car.

My dashboard was made of masonite or something. I added a couple coats of lacquer paint to it in case of water leaks. I didn't want the wood to swell.

Step 3: Create Holes for Nozzles

Decide on the placement of your misters. Choose carefully, because once the holes are drilled, there is no going back. As my mom used to say, measure twice cut once. In this case, measure twice, drill once per nozzle. Stick your nozzle through to check hole size is adequate.

Step 4: Cut Tubing to Size

NB: LEAKAGE IS A THING SO TAKE PRECAUTIONS!!! You don't want water leaking over electronics behind your dashboard! I found plumbers tape rather effective with my type of misting system. Without plumbers tape it was prone to some leaking, but by wrapping plumbers tape on the tube before inserting it into the T piece I had a good seal. Silicon was useless - I tried that first.

So now you will cut your tubing to the length necessary to join the nozzle T pieces. If you bought the same misting kit I did, be prepared to do some tedious labour to get the old piece of pipe out the T piece that joins the tubing to the nozzle. Then add plumbers tape and push the tube into the T piece. If you have a different type of misting system, it may work differently, and however you prevent leaks is up to you. But plumbers tape is a good choice obviously as it is designed to prevent leaks where joints and liquids are concerned.

You could also "zone" your system by adding a valve between nozzles, to stop the water from flowing further down the tube. I didn't, but in my final version I do plan to. I think it goes without saying that the nozzle should be downstream from the primary nozzles (being the drivers seat as far as I am concerned). If you were so inclined you could run parallel circuits and mist your passenger without misting yourself. But with mine, I wanted simplicity, so it runs in series and I would add a valve between the ones that benefit me and the nozzle that only benefits my passenger.

Step 5: Securing Nozzles and Replacing Dashboard

I created a bunch of brackets to secure the hosing which would in turn hold the nozzles in place. You can see one such bracket in the second photo on this step. While pondering how to attach these brackets in an aesthetically pleasing way... very small self tapping screws? glue? duct tape?.... I had one of those moments of genius.

I didn't need to secure the hosing, just the nozzles. and they were ever so slightly wider than their screw and rubber washer. Simply putting the washer between the nozzle and dashboard before screwing it into the T piece behind the dash worked out perfectly. If your dashboard material is too thick, perhaps you could consider carefully thinning it where necessary. I had no such issues. I'm sure the audience of this post can work something out.

Anyway, I loved the finished result.

Step 6: Test for Leaks

Attach the system to a water source with adequate pressure and make sure there are no leaks. If there are, fix them. I hadn't applied any plumbers tape to the last nozzle and had a leak there. I solved this by wrapping plumbers tape to it and carefully shoving it back in. Ideally if you have the excess tubing, just redo the tubing between the nozzles with enough plumbers tape and you should be set. I think I still have a slight leak behind there. But in this prototype I don't care enough to fix it because it is nowhere near any electronics that side of the car. I'll fix it when I get the higher pressure system and the real misting nozzles.

No leaks? Good. Almost finished.

Step 7: Reinstall Dashboard

So, I'd recommend leaving enough tubing coming out your dashboard (leading off from your nozzle that is destined to connect to your pressure system) that you can choose an appropriate place for your pressure pump bottle. I didn't and mine is now in my way when entering and exiting the vehicle. Learn from my mistakes. It's an issue I'll fix in my next iteration personally, but one you needn't suffer.

Step 8: Attach System to Pressure System

Preamble: My first attempt at this was very successful. I simply put the tubing over the nozzle supplied with the pump, put on some electrical tape and clamped it tight with a tube clamp (the kind with a strip of notched metal and a screw as seen in the image). I then thought I'd be clever and redesigned the system in much the same way as the T pieces worked. Tapered hole that is just a little thinner than the tubing using a drill into the orange screw fitting on my pump. I then replaced the large clear thing (essential for the pump to only spray when you press the button) and set off on my first venture. On day 1, I returned to the car and found the tubing had come loose from the pump. Luckily I had some duct tape on me and did a quick roadfix that is still in use now.

Recommended method: Fit the tubing over the brass nozzle on your pressure pump, put a little electrical tape over for grip and use a tube clamp and clamp on tight. This worked and looks better than what I have currently (as seen in picture), which is a variation on what I just said, except that I don't have the brass nozzle anymore so I just slipped the tube in, and duct taped the hell out of it with a clamp for good measure.

Step 9: How to Use

I think it's pretty self explanatory but fill container with water, pump the pump handle. Now it's primed for usage. then press the handle to make with the spraying!

Step 10: Cool (no Pun Intended) Ideas


Include some injection system with essential oils to add scents to your mist. I'll think on this once I have created v1.0 - The electronic pressure pump misting system.

Just imagine, driving past a chicken farm and spraying your car full of lavender or whatever you want to mask the smell. Just another reason this is better than air-conditioning.

Cooling additives

Ice in the container seems an obvious one - but it won't last long.

Anything that evaporates quickly:

NB: Both ethanol and acetone I'm sure have psychoactive effects when inhaled and or are hazardous to your health. So before I get berated in the comments I thought it's worth mentioning that this is probably NOT a good idea, considering you shouldn't drive while intoxicated. I mentioned it more in the hope that it would spark some comments about what additives one COULD use to create the same cooling effect without the risk of intoxication.

Acetone smells rather strong.

Alcohol might not be a great idea if you were to drive past a roadblock - although, it probably wouldn't affect your blood alcohol content when doing a breathalizer or such.

Freeze after sun product seems to use ethanol (alcohol) to give the cooling sensation - it evaporates quickly and makes you feel cold. It also contains menthol, which might have some effect.

Automatic pressurisation using your 12v tire pump

You could add a valve to the pressure bottle and attach the compressor pump usually used to pump tires that you may or may not have lying around for an automated solution that doesn't require you buying a liquid pump. So long as the bottle is pressurised the trigger should make with the spraying.

Fully automatic system

This is my plan for the next version I make. If only getting a high pressure 12v misting pump was simpler in South Africa. Anyway... Basically, mix this Instructables with

Which is exactly what I'll do for my next Instructables. At the flick of a switch I want mist. Preferably not too loud.

Perhaps I'll even have had the chance by then to experiment with some cooling additives by then, or I may even have come up with a system for injecting scents into the mix on demand.

Step 11: Troubleshooting

So these hand pump sprayer things. I'll just quickly run over any problems you may experience - or rather the ones that I experienced.

1. Escaping pressure from pressure release valve

You may find that after pumping you hear air escaping from the pressure release valve (First image). I had this happen after releasing pressure from the system a couple of times. The problem is that the rubber o ring had become unseated. Simply remove the valve by unscrewing it and place the o ring on correctly (Image 2) and replace the valve. To avoid this, should you need to release pressure, don't pull the release valve all the way. Honestly there isn't really a valid reason for using this valve anyway as if you want to fill up the bottle, just unscrew the main container from the handle.

2. System is pouring/spraying out water when I pump instead of just when I push the button

The system works by holding air pressure in the bottle and using that to push the water out when the trigger is pulled. When you pull the trigger, the pointy bit (Image 3) is pulled back from a clear washer thing (your may not be clear but it probably looks pretty similar to mine from images 4 through 6) and allows water to escape the pressurised container. If you have (like I had at one point) removed that washer thing, make sure you have put it back. Also make sure you put it back in the correct orientation. That is with the "nipple" facing the handle and pointy bit. This creates an adequate seal apparently.

Step 12: And Thus Ends My First Instructable

I hope you have enjoyed. I hope you make one better than mine. Soon I shall too.

As previously implied my plan is to put a tank in the boot with a pressure pump (>160 psi) and replace the nozzles with ones with smaller holes so the water particles sprayed out are fine enough to not leave me wet, but evaporate before hitting my skin, thus cooling the air without wetting me. I'd also like those to be the non-drip nozzles.... In this iteration of the system I will probably also install a valve to prevent the nozzle on the passenger side from spraying unnecessarily.

I have already installed a smaller gas tank to create more boot space to include a tank of water without reducing my already pretty limited boot (or trunk for you Americans out there) space.

I've been a fan of Instructables so long. It was just time to contribute. Let this be the first of many!

PS: I'm ordering the parts for V1.0. So expect an update soon.



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    2 Discussions


    6 weeks ago

    Pump should be here by the end of the next week. Perhaps I'll be updating this to V1.0 by the end of the competition ;)

    1 reply

    Reply 22 days ago

    Pump only arrived now! Don't think I'll have time. too busy building a NYE Rocket. Hmmm... perhaps another opportunity for creating an instructable