Testing the 24 Volt Warn VTC air compressor
I had a bit of spare time today so I decided to test Warn's claims about the VTC air compressor:
I am testing the 24V version of the VTC. I paid for and personally own the compressor and have received no sponsorship or any other considerations from Warn or any of its affiliates.
From the Warn website -
Warn Industries - Air Products: WARN Air-Power VTC
"With an abundance of power from its high-horsepower fan-cooled motor, V-twin configuration, and large one gallon integrated intercooler and reservoir, the Air-Power VTC is the highest-performance compressor in the WARN Air-Power lineup. The VTC is ideal for powering air tools, rapidly airing up everything from tires to rafts, powering air suspension systems, and just about anything else that needs air. It comes with a removable carrying cage so you can easily transport it or hard mount it to a vehicle or trailer. A pressure cut-off switch turns the compressor off when it reaches 100 PSI and back on at low pressure. Add to this a quick-connect hose outlet, and you've got an ultra versatile compressor. With all this power and all of these features, the VTC is a force to be reckoned with. "
Power: 12V DC motor
Maximum Pressure Rating: 100 PSI (690 kPA)
Airflow Rating: 20 CFM @ 0 PSI; 8 CFM @ 90 PSI; (566 l\min @ 0 kPA, 226 l/min @ 620 kPA)
Intercooler/Air Reservoir Size: 1 gallon (3,78 liter)
I did three basic tests -
1. Tire inflation using Coleman (my trail-rig BJ74) as the guinea pig since it has 33 x 12.50 R15 tires and I have outfitted this truck with a 350 Amp accessory plug for a second winch and the VTC compressor.
2. Running a 1/2" commercial grade impact gun to remove lug nuts.
3. Running a high volume die grinder continuously to check total air flow.
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Tire inflation -
I deflated a slightly warm 33" tire from 35 PSI to 5 PSI and measured the inflation pressure at the low end with an accurate low pressure gauge.
I attached a Napa inflator with gauge attached to the compressor and timed how long the re-inflation took to get back to the 35 PSI mark. The compressor was hooked up to the truck running at idle (about 800 rpm). The air hose on the inflator is only 1/4" ID.
From 5 PSI to 35 PSI took 1:31.0 and I stopped adding air to the tire on three occasions to check the pressure (total time to do that was probably in the 5 second range).
Performance thoughts: pretty much what my shop compressor would do given the air hose restrictions and time to check the inflation pressure. My shop compressor is capable of 18.5 CFM at 90 PSI. I think this is outstanding performance for a relatively small air compressor package, and is certainly much faster than other small electric air compressors used for similar purpose.
Removing lug nuts -
I attached a Mac Tools AW434 1/2" impact gun to the compressor via a 50 ft long 3/8 air hose. The gun operated extremely well for the short bursts that were required to remove the 6 lug nuts that hold on the wheel I tested.
Performance thoughts: I would have no issues using this compressor for these types of jobs, and I'll start packing my air tools again when I go out on longer trips. The AW434 is a full-sized commercial grade impact gun and uses a considerable amount of air.
Continuous use of a high volume requirement air tool -
I used a Mac die grinder hooked up the Warn 24V VTC air compressor via the same 50 foot air hose as above. The grinder worked at full speed until shortly after the compressor started, and then the performance dropped off as the compressor tried to keep up with the air volume required.
Performance thoughts: This was an unfair test in some ways as die grinders are major air hogs and the Warn VTC has a relatively small air reservoir, even with the length of air hose I was using. The performance of the die grinder was reasonable, and it could certainly get the job done but at slower speed than a large shop compressor.
Overall -
I am very pleased with the Warn VTC and its overall performance. The VTC is a somewhat large-ish package to be carting about, but having an abundant source of air that does not require under-hood modifications is very much worth it.
The compressor would certainly operate continuous use air tools much better if additional storage volume was added via under-body air tanks. On my old BJ42, I used a Chrylser V-twin AC compressor for many years with a 5.5" x 18" air tank and it had excellent performance - though the installation was time consuming. The VTC is comparable in many ways with the exception that the storage pressures that is working at were much lower than what I managed with my Chrysler unit.