Electric A/C compressor

Omni

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Good Day All
Never knew something like this existed. Anyone have experience with one of these set-ups?
Looking to install A/C on a Dodge P/U (I know not a C Body, but its big enough) with a /6.

Thanks to all who respond.
Omni
 
I'm thinking electrical draw would be excessive.

I had to look though and you might want to read this: Tech Topic: Is an Electric Compressor a Good Option for My Hot Rod?

"with some compressors drawing as many as 180 amps at 14 volts" That's a lot more than the high output alternators that are available.

IMHO, since it takes power to drive an alternator, and I think you'd be looking at adding a second high output alternator, any savings in engine power for not driving the AC compressor is going to be lost in having to drive those alternators. Then you have the added wiring and more complicated belt drive. I think you would be better off adding a conventional AC system. The modern Sanden compressors are lighter and take less power to drive than the old style compressors, so I can't see a lot of (if any) advantage.
 
My career is in the Automotive industry and I work for Toyota R&D. We use an electric motor for the a/c compressor in many vehicles but it runs on a minimum of 24 volts. If it would be efficient on 12 volts we would have done it. That being said if you still move forward I would install a second battery and high output alternator.
 
Perhaps doing electric power steering, higher-output alternator, and the Sanden compressor might be a better combination?
 
Thanks to all for your insight.
I was concerned about the increased electrical draw and what upgrades to the electrical system would be needed. The link provided by Big John certainly shed light on the subject. Thanks Big John.
The 'test mule' would be a one lung/6 manual trans 87 D150.
Seems like its asking a lot from a one barrel, looks like 1 need to source some 'Super Six' parts. At least I don't have to worry about the kick down linkage.
Carlisle swap meet, here I come.
Thanks again
Omni
 
Last edited:
Thanks to all for your insight.
I was concerned about the increased electrical draw and what upgrades to the electrical system would be needed. The link provided by Big John certainly shed light on the subject. Thanks Big John.
The 'test mule' would be a one lung/6 manual trans 87 D150.
Seems like its asking a lot from a one barrel, looks like 1 need to source some 'Super Six' parts. At least I don't have to worry about the kick down linkage.
Carlisle swap meet, here I come.
Thanks again
Omni

You can easily find a high current alternator even for a /6 225 in your Miser. Your thread interests me because I drive an '83 Miser D150, and was just discussing the possibility of using an electric Sanden AC on that some day. Regardless of HOW the power is delivered, air conditioning uses a LOT of it, for transient comfort. For a 225, an electric AC actually makes good sense, and I think a 200 amp alternator, suitably circuited would do the job, unless you load the rest of the truck with other parasitic electrical widgets.
 
You can easily find a high current alternator even for a /6 225 in your Miser. Your thread interests me because I drive an '83 Miser D150, and was just discussing the possibility of using an electric Sanden AC on that some day. Regardless of HOW the power is delivered, air conditioning uses a LOT of it, for transient comfort. For a 225, an electric AC actually makes good sense, and I think a 200 amp alternator, suitably circuited would do the job, unless you load the rest of the truck with other parasitic electrical widgets.
Thanks for the thoughts Gerald.
As I get older I find that A/C is no longer a 'nicety' but a must have (along with cruise control).
The article supplied by Big John was an eye opener. As with EV's it sounds like a great idea, but it is not perfected yet. When I add things like A/C and cruise control, I try to utilize as many 'off the shelf' and factory items as possible. Makes looking for replacement parts (if needed) a lot simpler.
For the A/C project the cost of a 'kit' or parts is about the same as a conventional R134 system, which I hear is going away for some 'new and improved' refrigerant. Add to that the cost of electrical upgrades, and it just isn't (at least for me) a viable alternative right now.
Omni
 
No reason to re-invent the wheel. There's a good reason why A/C compressors are belt driven. (often 2 belts)
 
No reason to re-invent the wheel. There's a good reason why A/C compressors are belt driven. (often 2 belts)
Centrifugal /scroll a/c compressors are very efficient.
Remember, every time one form of energy is converted to another, there’s inefficiency.

If you used an electric a/c system, there’s two conversion losses there (rotating to electric in the alternator) and electric to refrigerant (in the electric compressor). Those inefficiency losses are heat and inherent losses.

In a mechanical compressor, there’s only one conversion losses (rotating to refrigerant). And the centrifugal/scroll compressor is the most efficient way.
 
Thanks for the thoughts Gerald.
As I get older I find that A/C is no longer a 'nicety' but a must have (along with cruise control).

I know some of that feeling, having just rolled over another year in my seventh decade, BUT, having been born in a frying pan, and matured in the same, I just adapted to it like the reptiles around me.

The article supplied by Big John was an eye opener. As with EV's it sounds like a great idea, but it is not perfected yet. When I add things like A/C and cruise control, I try to utilize as many 'off the shelf' and factory items as possible. Makes looking for replacement parts (if needed) a lot simpler.

Ditto. COTS remains my modus.

For the A/C project the cost of a 'kit' or parts is about the same as a conventional R134 system, which I hear is going away for some 'new and improved' refrigerant. Add to that the cost of electrical upgrades, and it just isn't (at least for me) a viable alternative right now.
Omni

Yeah, from what I've read, retro-fitting electric AC DOES require a serious high current system. A miser really would need at bare minimum a 200A alternator to run such, and just keep the battery charged DURING THE DAY. If one had to run those big ugly square headlights our old Dodges use on top of keeping the cab cool, then worry about that battery would have to crop up. Does your D150 come w an auto-trans, or is it pure-dee manual like mine?

Anyway, you'd best look at a belt driven compressor, given all the data here.
 
Gerald
Mine is a /6 4 speed (O.D.) with single square (retangular) headlights. Once I find a decent carb, it will be much better. The 1945 pollution controlled Holley just doesn't idle well. looking at either a 1920 Holley or a BBS Carter.

Omni
 
Gerald
Mine is a /6 4 speed (O.D.) with single square (retangular) headlights. Once I find a decent carb, it will be much better. The 1945 pollution controlled Holley just doesn't idle well. looking at either a 1920 Holley or a BBS Carter.

Omni

Stick w the Holley for this setup. Yours is practically identical w mine, despite a few yrs difference. I found a 1974 Holley 1945 which has served pretty admirably, though I long for a Super 6 intake and a good 2 barrel carb for it. Usually, I prefer Carter carbs, but for the purpose of "de-Lean Burning" our Misers I found the early 1945 to be a better deal than a 1920. 1920s spill their bowls too easily to make a safe pickup truck carb.

I've speculated on a full up DIRECT fuel injection system for a /6 225, NOT the cheap crap Holley sells for I-6 engines. The Aussies make them, just as they do long rail 2 and 4 barrel intake manifolds. All it takes is a little Time and a bail of money....

I've also looked at getting a brand new, modern 1 barrel carb for Wilhelm. I've chatted with Daytona Parts about using one of their carbs. But for the present, the 1945 I put on does very nicely. That likely will be your easiest bet.

One more thing: you might need to re-circuit your starter switching a little. The Lean burn board did part of that chore with these, and when I eliminated it, I had to put an additional relay in to get a good start and run. I'm curious about whether you will need to do likewise.
 
Stick w the Holley for this setup. Yours is practically identical w mine, despite a few yrs difference. I found a 1974 Holley 1945 which has served pretty admirably, though I long for a Super 6 intake and a good 2 barrel carb for it. Usually, I prefer Carter carbs, but for the purpose of "de-Lean Burning" our Misers I found the early 1945 to be a better deal than a 1920. 1920s spill their bowls too easily to make a safe pickup truck carb.

I've speculated on a full up DIRECT fuel injection system for a /6 225, NOT the cheap crap Holley sells for I-6 engines. The Aussies make them, just as they do long rail 2 and 4 barrel intake manifolds. All it takes is a little Time and a bail of money....

I've also looked at getting a brand new, modern 1 barrel carb for Wilhelm. I've chatted with Daytona Parts about using one of their carbs. But for the present, the 1945 I put on does very nicely. That likely will be your easiest bet.

One more thing: you might need to re-circuit your starter switching a little. The Lean burn board did part of that chore with these, and when I eliminated it, I had to put an additional relay in to get a good start and run. I'm curious about whether you will need to do likewise.
Gerald
Mines starts in about 1/2 revolution of the starter. Easiest /6 to start that I've owned (and i have owned many). Idles great when cold but as it warms up the idle is erratic at best. A timing light shows the timing to be right on, no deviation.
I have soaked/rebuilt the carb (1945) replaced the float with a brass one, no amount of tweaking seems to have any effect.
 
Gerald
Mines starts in about 1/2 revolution of the starter. Easiest /6 to start that I've owned (and i have owned many). Idles great when cold but as it warms up the idle is erratic at best. A timing light shows the timing to be right on, no deviation.
I have soaked/rebuilt the carb (1945) replaced the float with a brass one, no amount of tweaking seems to have any effect.

Oh when a carb wears out, it becomes scrap metal. The 1945 I got with the truck probably can be rebuilt with a modern kit and will be good again, but I've been very fortunate with this 1974 build. The throttle return setup on those is preferable to later, Lean Burn stuff.

If you're not off-roading, a 1920 doubtless would be safe enough, as that was the '45s predecessor. I see the dearth of 1 barrel carbs for Mopars hasn't improved in the 4 years since I de-Lean Burned. I might try one of those Daytona carbs as an option sometime. Plenty stuff for Fords and Chevies, which probably can be made to work if one must also, though still, NOT TOO plentiful.
 
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