A\C powered by traction or 12v battery?

high voltage, a 12v could never power anything that energy intensive

 

Traction battery only. I use mine every afternoon and on extremely damp and foggy London mornings. During winter too, for defogging the windows.


iPhone 6s +

 

The compressor for the air conditioning system is run off the high-voltage supply.

Everything else (fan, controls, supplemental electric heat while engine warms up) runs off the 12 volt supply.

 

are those priuschat threads?

 

They're probably just writing casually, and not as interested in the exact details of that as in other aspects of their camping setup.

 

When you are parked in the Ready mode with the AC on, the traction battery will run down and the car will start and recharge it (takes about a minute or minute and one-half). I am sure the 12 volt is engaged in some manner, but the traction battery is the main power for AC.

 

As it was in #4, the high-voltage system is the power source for the A/C compressor, and the low-voltage system the power source for all the rest of the HVAC components.

And of course, when the car is in READY, the high-voltage system is the power source for the low-voltage system. All of it is kept charged by running the engine as needed, which happens automatically.

 

Everything about the HVAC except for the A/C compressor itself is run off the 12 volt system.

When the engine is warm, all of the heat from the heater is being extracted from hot coolant from the engine.

While the engine is warming up, some minimal heat comes from electric elements inside the HVAC unit, powered from the 12 volt system, and only totaling about 700 watts. Compare that to the 5300 watts worth of heat that can be extracted from the coolant when the engine is at temp. The 700 watts are more or less imperceptible in a cold car, except for sometimes helping the windshield defog a bit noticeably faster.

 

Hi Chapman, I replaced a bad transmission in my 07 touring model and after the swap my AC comp doesn't pump. Everything else seems to work like it should. Any ideas on what to check first?
There is pressure in the system, about 95 psi on both sides, so I don't think there was any freon loss.
Thanks in advance for any advice/ideas,
Gary

 

Maybe the high-voltage (orange) power connections between the inverter and the A/C compressor weren't correctly remade after the transmission work? (Don't just grab them to check. They're high voltage.) Maybe another related low voltage connector was overlooked.

There is a method for getting trouble codes from your A/C computer without even needing a scan tool. If I remember right, it involves holding down AUTO and RECIRC while powering the car on, then you look for two-digit codes in the corner of the MFD. If it can't run the compressor, it has probably noticed.

Anything that involves opening the sealed system, evacuating, recharging, I would probably save for later, after making my best use of non-invasive ways to identify the problem.

 

With fresh eyes (and brain) this morning I found one of the connectors behind the inverter didn't get plugged back in. It was the black one with about 6 wires in it, and of course the hardest to see! Just goes to show you that we should start with the simple stuff until you can pinpoint the problem.
Anyway, everything working swell now! Thanks for the help!!

 

Bumping this thread - I just successfully reconditioned my battery, so I am in test mode. Had to replace ECU due to corrosion. As I'm testing it, kept A/C off to get it to charge to high SOC. All good, but turn A/C on and it blows fine, no codes, but is not cold. Been sitting dead for two months as I played with batteries, is there anything I may have missed in reinstallation of the battery that would stop the compressor from working?

 

If you have a capable scantool, you can check the HVAC ecu for codes and watch compressor RPM when you turn the system on.

I would expect most HV faults to set warning lights and HC or HVB codes.

Really, if I had a "no cooling" complaint, I would get a gauge set connected to the A/C service ports and see what the high and low side pressures are. Would not be surprised if you have a leak somewhere.

Posted via the PriusChat mobile app.

 

Or have dealership do an "AC Service"? Only disclose that it's not cold, methinks.