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The most important thing to the conversion, when you start changing refrigerants, is the thermostatic expansion valve, or txv. This is the metering/restriction device that controls the flow of refrigerant into the evaporator. It is attached to the evap inlet and a sensing bulb on the outlet that controls it. It also prevents liquid from hitting the compressor, slugging the compressor and destroying the valves. They are set up for different pressures for different refrigerants and temperature ranges.
To get all the oil out of a system, you have to remove components, like the compressor and pour out the oils. Then, clean and flush. To do it right, is difficult and time consuming. Also, you need to make sure you have enough condenser heat rejection and evaporator heat absorbtion. its actually a carefully balanced system. Youre best bet, IMHO, is to reuse all the components, only changing the means for running the compressor. (belt, seperate motor, hemetically sealed electric) There are freon and oils that are compatible, and then there are some that will turn into a thick sludge and plug up the system.
Have fun experimenting!
 

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most home air conditioners (central or window) use r-22. As JRP said, R-134a replaced r-12 years ago as it was blamed to deplete the ozone layer and it was banned to manufacture it. If you were to use this unit, it would more than likely need r-22. (which btw, both r-22 and r-134a are planned to be replaced also with more envionmentally friendly gas, possibly CO2) Also by the way, you need a EPA license to purchase R-12, and technically a special class of the EPA license to fill this unit in a vehicle.
Mike
www.EV-propulsion.com

AS of a few years ago the EPA also regulates R22, we had to check EPA license to sell it to a customer.
 

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I just have a large ice/water tank that circulates through my A/C core using a regular winsheild washer fluid pump. It's not powerful, but it blows cool air for a few hours.

I'll upload a photo of my fill hole (on the hood) -- you don't have to open the hood to add ice, just the ice fill door.
 

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Neat idea, are you at all concerned about corrosion of the A/C core? They weren't designed for water.
I think he means the heater core, or at least the heater core would be ideal. The a/c core probably couldnt flow enough water.
I do like the heater core/cold water idea. Gives you a heater and a cooler, but then you have to heat and cool the same water somehow. There was a good idea somwhere.
I'm going to try wrapping freezer gel packs around my heater tank with some insulation and see how that works :D Should be able to pump some cold water through my heater core for a while, though condensation may be a problem.
There it is, I like it!
 

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I think he means the heater core, or at least the heater core would be ideal. The a/c core probably couldnt flow enough water.
I asked because I actually did that once in an old ICE. The heater core was bad and it was major surgery to get to it, and I didn't have a lot of cash. The A/C system had been removed so I just hooked the heater hoses to the A/C core. It worked well for a while, until that too went bad and started leaking.
I do like the heater core/cold water idea. Gives you a heater and a cooler, but then you have to heat and cool the same water somehow. There was a good idea somwhere.

There it is, I like it!
I actually gave it a half hearted attempt the other day after a week of 90+ temps. It did give me a few minutes of cool air but not enough. Problem is I needed to wrap the tank, let it sit and cool down for a while, then put on fresh frozen gel packs when I was ready to drive. Plus probably should have wrapped insulation around it too. Instead I gave up and jumped in my ICE car and turned on the A/C. :eek: Luckily we don't see 90 around here for more than a few days, normally.
 

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Neat idea, are you at all concerned about corrosion of the A/C core? They weren't designed for water.
The core is aluminum, so yes, it will eventually rot out... but by then I would have already gone through three battery packs anyways.... :D

and besides, after it starts leaking, I can always switch the hoses over to the heater core for as long as that lasts ;)
 

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I have a couple of questions for you guys:

1. Do any of you know how much cooling power an air conditioning unit in puts out in a EPA rated mid-size car?

2. Do any of you know how much power it takes to turn an automotive rotary A/C compressor versus a piston type?

Best regards,

Bob
 

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I have a couple of questions for you guys:

1. Do any of you know how much cooling power an air conditioning unit in puts out in a EPA rated mid-size car?

2. Do any of you know how much power it takes to turn an automotive rotary A/C compressor versus a piston type?

Best regards,

Bob
1. I've read 1-3 ton, but have no solid numbers.
2. Do you mean scroll vs piston?
power required to turn depends on load and engine speed.
 

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I am reminded of what my father used to do by a recent full page newspaper ad touting the most efficient air conditioning.

Not sure if anyone else noticed this but they are actually selling boxes that you place a block of ice in that have a fan on top with ice on top, the air is forced over the block of ice and through a mesh that has the melt water on it. My father used to use a block of ice on really hot days coupled with a fan years ago, rather surprized someone is marketing it

But that said might be worth thinkin about, heck on hot days I take those large gel filled ice compresses we had from surgery and wrap them over my sholders.

Look outside the box, there are cheaper and oddly enough more effective ways of staying cool than wasting 50% of your range on AC.

That said I often wondered if the old edison, designs with no moving parts would work off of solar heat on your cars roof.

Cheers
Ryan
 

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Problem is those other methods don't lower humidity and can actually raise it which makes things more uncomfortable.
Not just more uncomfortable, but also, the higher humidity can penetrate the wiring and electronics (such as the radio....you all DO have tunes, right?) causing corrosion, shorts, and other nefarious and sundry issues (things like corroded door locks and latches, corroded power window motors, if equipped, etc.).

All in all, a really, REALLY bad idea for an automobile.
 

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Not just more uncomfortable, but also, the higher humidity can penetrate the wiring and electronics (such as the radio....you all DO have tunes, right?) causing corrosion, shorts, and other nefarious and sundry issues (things like corroded door locks and latches, corroded power window motors, if equipped, etc.).

All in all, a really, REALLY bad idea for an automobile.
Actually my car did not come with a radio, it was an optional component.

LoL nothing like being draconian, you do realize much of your engine compartment and everything in it gets wet during rain?

You do realize the insides of your doors get wet each time it rains as that is where the rain is channeled through off the window?

Vehicles are designed to be moderately reliable in the presence of water because water is unavoidable in most areas of the car except the inner cabin and trunk.

I think you believe I was talking about putting a saltwater mist in the cabin, that would accomplish what you state.

Also Door jams on cars are designed to get wet now and again and I have never seen one rust, I have seen the floors rust out but never a door jam, even on cars by the ocean mists out east. But then again the hinges on my 1970 subaru are a bit rusty but they are also on the outside of the car and the car is 40 years old. Nothing enough to cause a functional issue though.

Cheers
 

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Actually my car did not come with a radio, it was an optional component.

LoL nothing like being draconian, you do realize much of your engine compartment and everything in it gets wet during rain?

You do realize the insides of your doors get wet each time it rains as that is where the rain is channeled through off the window?

Vehicles are designed to be moderately reliable in the presence of water because water is unavoidable in most areas of the car except the inner cabin and trunk.

I think you believe I was talking about putting a saltwater mist in the cabin, that would accomplish what you state.

Also Door jams on cars are designed to get wet now and again and I have never seen one rust, I have seen the floors rust out but never a door jam, even on cars by the ocean mists out east. But then again the hinges on my 1970 subaru are a bit rusty but they are also on the outside of the car and the car is 40 years old. Nothing enough to cause a functional issue though.

Cheers
Yes, I stated exactly what I meant-after over 30 years of designing vehicles (civilian and military) I have seen a "few" problems from moisture. There is a reason military electrical systems use Cannon plugs, and civilian vehicles use Weatherpac connectors.
 

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