Can running the blowers for the AC with the engine off drain the battery?
I have gone out to my car on my 45-min lunch break several other times and used the radio and the AC blower fans to move the air in the car and have not had any issues with a dead/weak battery. Today I went out and used the blowers for about 45-min while I did some work on my laptop. It made the battery so weak that the starter motor would turn but not enough to crank the engine. I left the car sit for a few hours and when I left at the end of the day, it started fine. Will running the AC blowers really draw that much battery power to drain it that much? I've done it before with no issues
Experienced mechanics share their insights in answering this question :
The problem is although the current draw over 45 minutes might be "low", your battery might be weak, meaning it could have a bad cell and a low reserve capacity. It doesn’t take much to "drain" a weak battery. A confusing thing though is your car is only a year or two old thus making a weak (i.e., "old") battery hypothesis, well, weak. Nevertheless, the thing to do is have your battery load tested (any battery shop will do this for free) to determine its actual condition. If it passes the load test (ask for copy of results so you can see the margin by which it passed), it is possible you have excess current draw in your car’s electrical system. Also consider the possibility that during your most recent break, maybe you inadvertently turned the headlights on which would add to the discharge. Get your battery tested, and if it is OK but the starting difficulty returns, a certified technician from YourMechanic, can diagnose your electrical system.
How to Identify and Fix Common car Problems ?
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Turning on the AC puts an additional load on the entire system resulting in the deficiency in the charging system further draining the battery.
Because at idle your alternator does not produce enough electricity to run the blower motor. If you give it just a little gas to increase the motor rpm. To a high idle it should then be producing enough electricity to run the blower motor without draining your battery.
Most AC compressors are driven from the powertrain, not the battery. The only thing electrical about them would be the clutch to engage the compressor. This shouldn`t drain your battery. Furthermore, if a car has an electrical compressor, it would not run off of the 12volt battery.
Car batteries operate on one-way direct current (DC) electricity, while alternators output alternating current (AC) electricity, which occasionally flows in reverse. [8] So prior to going to the voltage regulator, power intended for the battery goes through a diode rectifier to turn into DC.
A single 12V 280 Amp Hour Dakota Lithium battery will run a 14,000 BTUs air conditioner for 2-3 hours.
Bumping up the heat or air conditioning for comfort while driving takes more energy from the battery. Controlling the interior and battery temperature is the biggest power drain second to driving the vehicle.
There is a 110 volt and 230 volt blowers in the industry today, and so the packs are equipped to be able to run both of them.
Your 30 watt fan will draw about 2.5 amps at 12 volts (2.5 times 12 is 30). Assuming 90% efficiency from the inverter means that the inverter will draw 2.5/. 9, or 2.78 amps. A 50 Ahr battery will last 50/2.78 or 18 hours.
Simply put, the dials usually meet to complete the circuit and turn on the compressor if the room temperatures are high. However, if they`re stuck, the compressor will keep on running even after the ideal temperatures are attained (air conditioner switched off).
The actual output voltage produced by the alternator will typically be about 1-1/2 to 2 volts higher than battery voltage. At idle, most charging systems will produce 13.8 to 14.3 volts with no lights or accessories on.
You cannot run the AC without the engine running. The air conditioner compressor and clutch are operated by the serpentine belt that runs your other accessories (your alternator, for instance). If the engine isn`t running, then the belt isn`t turning. That means your air conditioner`s not actually on.
As long as the engine is running and you aren`t running low on fuel, you can keep your car idling with the AC on for as long as you`d like. .
Even though most car batteries are only 6 or 12 volts, a 12-volt battery can produce as much as 600 amps.
We`ve worked out that the air conditioner will use up 62 amps to maintain the temperature for one hour. We have a 400Ah lithium battery and 400W of solar providing power. So you could run this air conditioner for roughly 5 hours using 400W solar and half your 400Ah lithium battery.
“Electrical devices or lights left running, a defective charging system or alternator, and extreme weather are some common reasons but maybe it`s just time to get a new battery.”
The single biggest drain on your battery, other than actually driving, is climate control. Whether that`s keeping you cool in summer or toasty in winter, systems typically require about 3-4kW to run, which equates to seven miles of range per hour to run the air-con and five miles per hour to run heaters.
A typical AC fan motor uses about 500 watts when it`s running. Therefore, if you run the fan continuously for a 30-day month (720 hours), you would use 360,000 watt hours (720 x 500) or 360 kilowatt hours (kWh).
Motor Power – For corded electric leaf blower, the motor power is measured in amps (A) and volts (V) is used to measure motor power of cordless leaf blower. For corded model, one can find options for motor powers as 7 amps or 12 amps, in which the 12 amps motor will offer better performance.
A standard fan motor will typically use about 400 watts per hour while a variable-speed model will only use 75 watts per hour.
Power is the rate of work in a time: P = F·v, where P = power; F = force; and v = velocity, ft/min.
In general, the larger and more powerful a leaf blower`s motor or engine, the higher both the blower`s CFM and MPH ratings will be. These ratings are also influenced by the impeller, which is the fan-like part inside the blower that creates the airflow.
A 12-volt power inverter will allow you to connect standard 120-volt plug in appliances, such as a fan, to your car battery.
The battery life of ALLOYMAN 20V 4.0AH is up to 20~40 minute (compared to twice that of other batteries). Fast charging technology can fully charge the battery within 1 hour.
Modern air conditioning units are designed to run 24 hours a day. There is no harm in having it run to keep your home cool all day long. If you wanted to, you could have your AC unit running 24 hours a day, seven days a week. If your thermostat is set on “auto”, your AC compressor does not run 24 hours a day.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Can running the blowers for the AC with the engine off drain the battery?
ANSWER : The problem is although the current draw over 45 minutes might be "low", your battery might be weak, meaning it could have a bad cell and a low reserve capacity. It doesn’t take much to "drain" a weak battery. A confusing thing though is your car is only a year or two old thus making a weak (i.e., "old") battery hypothesis, well, weak. Nevertheless, the thing to do is have your battery load tested (any battery shop will do this for free) to determine its actual condition. If it passes the load test (ask for copy of results so you can see the margin by which it passed), it is possible you have excess current draw in your car’s electrical system. Also consider the possibility that during your most recent break, maybe you inadvertently turned the headlights on which would add to the discharge. Get your battery tested, and if it is OK but the starting difficulty returns, a certified technician from YourMechanic, can diagnose your electrical system.
Battery drains quickly, New battery,Heavy drain, Replaced alternator , drain still there,goes away when bat. main 2 fuse is pulled
ANSWER : Hi there. It’s quite possible that you have one of two things causing the drain to the battery. First, you have a bad ground somewhere in the main relay or fuse box or an exposed wire somewhere that is not allowing the circuit to complete from the alternator to the battery. This can cause a battery draining issue as you’re describing, but it could also be one of multiple other electrical problems. The best way to pinpoint the exact source is to have a professional mobile mechanic come to your location and complete a battery will not hold a charge inspection.
Honda Civic 2008. AC stopped working suddenly and engine check light came ON for a day.Next day AC worked and no engine light.
ANSWER : Hi there. In both cases, when an AC system is not working and a warning light is coming on the dashboard, typically a professional mechanic will complete the same initial inspection, which is to download the stored error codes that triggered the warning light initially. This tends to give them an idea as to what is causing the problems. This could be something as simple as an electrical relay that is faulty or loose or an indication of a computer related "glitch". Either way, the best way to move forward is to have a professional mobile mechanic complete a check engine light inspection.
Battery light stays on and overnight battery drain. 2006 Land Rover LR3
ANSWER : Hi there – yes, something is going on here that’s draining your battery. Perhaps the pressure of the engine wash dislodged wiring which has shorted, or there was a chemical reaction to the cleaning solution that caused electrical damage in the alternator or voltage regulator. These componnents can be checked off of the vehicle. Vehicle wiring can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and replace/repair the failing component.
Battery light stays on and overnight battery drain. 2006 Land Rover LR3
ANSWER : Hello – this problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and identify, replace or repair the failing component.
The engine of the car runs, but when I push the gas pedal it does not accelerate, and the engine does not rev.
ANSWER : Hello. It sounds like you may have an issue with your throttle position sensor. This sensor sends a reference voltage to your power-train control module, which uses that to determine ignition timing and fuel trims. If the power-train control module is not detecting the proper signal from the throttle position sensor, the engine may not accelerate properly. It’s probably a good idea for you to have a professional mobile mechanic come to your location and complete a car is slow to accelerate inspection first, so they can pinpoint what is causing this issue to occur and they will recommend the right repairs be completed.
I have Chrysler 300c. Battery light came on, changed battery and alternator but power still getting drained and battery light still comes on.
ANSWER : Hi, thanks for writing in. This may be a sign of a failing starter relay. The starter relay is a small unit near the starter that directs power to the starter from the battery. When this fails, it may cause a clicking sound and will not allow the starter to engage the flywheel when you turn the key. I would suggest having a professional from YourMechanic come to your home to diagnose your starting issue to determine the solution to get you back on the road.
When the AC is turned on my Check engine light comes on , code reading throttle position sensor, not enough voltage.
ANSWER : If you have the electronic type throttle that has no cable to the throttle body, then you will need to check to make sure that battery voltage is not dropping below 12.5 volts when your A/C is turned on. You will need to have the charging system checked to make sure it is putting out above 13.2 volts at idle and the amperage at 1500 is within specified range of 87 amps and that the voltage does not drop below 13.5 with no load.
You may be overloading the alternator with the stereo amps you have and causing the battery voltage to drop too low at idle causing the throttle actuator to not work correctly. The A/C takes about 20 amps of power to run and if you are already taking more than the alternator can put out at idle, then the only place to get the power is from the battery. The battery is rated in AMPs not volts. You put a heavier duty battery that has more amp capacity and if the alternator cannot replace the power taken away, then the voltage will drop in the battery until it gets below the 12 volts needed to power the electronics in the car and there’s where you will start to have problems. If you want to have this diagnosed in person, a technician from YourMechanic can inspect your Check Engine Light and let you know exactly what will need fixing.
