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View Full Version : Why do little compressors go so high, 200PSi



Bill Dufour
07-18-2022, 8:58 PM
I have noticed that the little compressors seem to go to a very high pressure like 200 psi. they have no tank so increase in storage is not the reason. Is it just marketing hype? The higher pressure means the pump produces less volume at usable pressure because the diameter of the cylinder must be reduced so the motor can handle the higher max pressure. I did buy one once because I needed the 200PSI to test an evaporator.
Bill D

My stationary compressor I reduced from 175 to 120 PSi for noise reduction. I did not increase RPM, but I could have. I can live with the slight storage reduction.

Richard Coers
07-19-2022, 12:29 AM
What kind of compressor has no tank? Only thing I've seen without a tank is an airbrush compressor.

roger wiegand
07-19-2022, 7:43 AM
I don't know about little compressors, but I do have a hard time inflating my truck tires to 80 psi with my compressor that maxes out at 110-120. Takes forever to get them from 70 to 80, not enough differential it seems. A compressor that goes higher does it without a problem.

Ronald Blue
07-19-2022, 8:41 AM
If there is no tank then what are these used for? Use a regulator for useable pressure. That would be necessary for many applications anyway. Higher input pressure means more pressure to work with when a storage tank is in play. My last work truck had a screw type compressor. Other than the noise that thing was amazing. Using a high flow air wand cleaning out radiators and things like that it would maintain full pressure (140 PSI) as long as you wanted to use the wand. When you released the grip it dropped back to stand by mode in seconds. Not unlike the portable compressors used for jack hammers and things like that.

Maurice Mcmurry
07-19-2022, 9:03 AM
Good piston compressors that produce pressure over 120 PSI Are generally two stage. Cascade compressors that go very high have multiple stages.

Bill Dufour
07-19-2022, 9:23 AM
I mean those little 12 volt compressors to fill a tire. Often have a flash light and blinking red light included.
Bill D

Jared Sankovich
07-19-2022, 10:11 AM
I mean those little 12 volt compressors to fill a tire. Often have a flash light and blinking red light included.
Bill D

I don't think those can go to 200. The gauge might but the pump won't.

Malcolm McLeod
07-19-2022, 10:14 AM
I mean those little 12 volt compressors to fill a tire. Often have a flash light and blinking red light included.
Bill D

I spend a good bit of time around compressors, but not the above, so take this for what its worth…
I suspect they design these to cover as many vehicle tire pressures as possible, even a semi running ~100psi range. So the compressor uses a small high speed 12V motor to get enough usable torque, and still keep within manageable amp draw. Then toss in a small diameter piston (to lower the demand torque). And now to get any flow rate at all at 100psi delivery, they have to be generating 200psi. …Maybe.

But I’m betting you knew this… ;)

George Yetka
07-19-2022, 11:20 AM
Can they truly go to 200 psi? or does the gauge go that high? The most accurate section of a gauge is at its mid point so a 50lb system, will normally have a 100 lb gauge. I usually dont 15/20 amp compressors going past 125psi or so. For air testing pipe we usually have to bring in a gas powered compressor as any plug in we look at wont get us to 150 psi or so. We test 1.5x working pressure in most cases.

Greg Funk
07-19-2022, 12:17 PM
I don't know about little compressors, but I do have a hard time inflating my truck tires to 80 psi with my compressor that maxes out at 110-120. Takes forever to get them from 70 to 80, not enough differential it seems. A compressor that goes higher does it without a problem.What size tires need 80 psi? Sounds like a bicycle tire :)

Jerome Stanek
07-19-2022, 12:28 PM
What size tires need 80 psi? Sounds like a bicycle tire :)

My F250 and F350 need 80 PSI in their tires

Scott T Smith
07-20-2022, 6:34 PM
What size tires need 80 psi? Sounds like a bicycle tire :)

All of my Load Range E 16" rim trailer tires are inflated to 80 psi.

The 19.5" rims on the F450's require 90 for the fronts.

Jim Becker
07-20-2022, 7:01 PM
I'm really not convinced that the small, portable (and often 12v or battery powered) compressors are really suitable for higher pressure truck and trailer tires. Even though they may achieve a high output pressure, the volume is so low that it might be an interminable process. The little compressor on the battery pack that Professor Dr SWMBO bought for treating her bee hives with a few years ago takes a ton of time to just get a rear tire of my ZTR up to only 20 psi...I got stuck using it for that last summer when my shop was shut down and I discovered one tire was very low while mowing the old property.

Greg Funk
07-20-2022, 7:29 PM
My F250 and F350 need 80 PSI in their tires

Guess you can tell I don't drive a truck!

Malcolm McLeod
07-20-2022, 11:21 PM
My F250 and F350 need 80 PSI in their tires

First time I needed to add air to a Chebby 2500 I drive in the field, I whipped into the nearest gas/grub emporium - - and started airing up the low tire. It took a few seconds to realize my tire was airing up their compressor.:confused::o

I tried 3 more stations before I found one that the air went in the right direction.

Tom Bender
07-31-2022, 8:09 AM
For car tires I use a hand pump. Good exercise and quiet. I keep a compressor in the basement but it takes something more than one tire to motivate me to carry it up the stairs.

Mitch schiffer
07-31-2022, 9:03 AM
My trailer tire take 108 psi. It still takes a while to get up from 70 psi to 100 psi even with my compressor that stops at 160.