I have a 33 gallon vertical craftsman air compressor. the motor is on top of the tank. My question is- can I run the compressor with out harming it while it is laying on its side.

I can't afford to try to sell it and buy a horizontal compressor.

The reason for this question is- I am building a new shop. I just had an idea of putting my air compressor in the attic of the shop and pluming my air to various locations in the shop.

The benefits would be less noise and take up less space.

 

No. The drain won't work, the compressor won't be properly oiled, and chances are you won't get good air circulation up there for proper cooling.

 

Yup,,, What Jared said. An engine simply doesn't work well on it's side!!! Tip your truck over and see how long it runs!! Ha! Ha!! Ha!!!

 

I wouldn't suggest it,but might be possible if the compressor is oil less like my 26 gallon craftsman. like jared said,you wouldn't be able to drain it unless you wanted to go to the attic and tip it upright every time it needed drained. how big is the shop you are building going to be? my garage is only 24x24 and my craftsman doesn't take up much room in the corner.

 

Why not just put it outside in the back??

 

Mount the compressor so it is in the position you want and replumb to the tank. Makke sure you put a new drain in on the lowest point of the tank. Fab up the holders you will need and put some casters on it to move it if needed. Run tubing around the shop for outlets if hose length is a problem. Run a water trap/filter on the outlet.

 

as the others said, its likely oilless, but you can unbolt the motor and run a new output line to the tank.

and most craftsman 115v compressors with the bigger tanks can also run 220v - motor life is greatly enhanced if you do this.

btw I was going to sears one day 3 or so years ago and passed a 7.5hp, 60 gallon someone bought and brought back. it was $150 off, so into the back of the s10 blahzer it went (on its side, was oil free at the time). I wired it up and plumbed the shop on 3 walls and the ceiling with 1/2" galvanized pipe with traps everywhere and dryers. best move I ever made. I was killing my old 3.5hp 30gal using it commercially when the cutoff tools came out. it might seem like overkill for a single home user, but its a marginal cost increase

 

Thanks guys for the response. The compressor is the oiless type.
I like the idea to relocate the motor, I think I could do this pretty easy. I wouldn't have to move the drain, I could still turn it almost vertical and drain it pretty good. I am only short in the attic about 4 inches to stand up the compressor.

I have built the shop 18x18 because of the concrete pad that was on the property when I purchased it.

I really don't want to put it out side, I don't have a concrete surface to set it on. Also, I like the idea of it being out of the weather.

As far as cooling for the compressor, I am doing this because it is the same way that my father's shop is. He uses the craftsman 26gal compressor. His is mounted vertically. He hasn't have any problems with it being in the attic. The attic is fairly well ventilated. The shop is directly under a big tree. I probably wouldn't try this in south Georgia where I used to live. It was way too hot. Here in the hills of TN its not that bad.

 

This is flat out wrong. A dual-voltage motor is internally wired so that the windings only ever see 120V(nominal). The windings are wired in parallel when hooked to 120V and wired in series when hooked to 240V. Thus, the amperage through the windings is the same either way, so there is no difference in motor temperature or life.

Jason

 

I think you are wrong about this. If a motor is wired 220 it will pull less amps. the less amperage it pulls the cooler it will be. This is true with electric winches as well when they are wired to run 24volts instead of 12volts. I have worked in poultry houses most of my life. every single poultry farm in the nation wires their fans to run with 220. these guys have it figured out, they have to because a single poultry house can have as many as 20 electric motors per house. some farms have up to 40 houses. motor are not cheap, that is why they run 220 volts.

 

You need to re-read my post, then. The windings in any dual-voltage motor never see more than 120V. The reason is that there are two sets of windings. If the motor is wired for 120V, then those windings are wired in parallel inside the motor so that each winding only gets 120V. When someone comes along and re-wires for 240V, then the terminals inside the motor have to be re-configured with jumper wires such that the windings end up in series so that 240V is applied across 2 windings. Ohm's Law applies: V=IR, or I = V/R. If you double the voltage, but also double the resistance (2 windings in series), then the amperage remains constant.

BTW, if we're going to toss around qualifications, I was in electrical engineering for a couple years in college before I pursued other interests. I'm also into woodworking and actively participate in several woodworking forums online that hash this very thing out from time to time since many woodworking machines have dual-voltage motors. The advantage on small motors is very insignificant. On a larger motor, 240V can be more cost effective in that you can run a smaller gauge of wire since the amperage in the supply wire is halved.

Jason

 

I don't know why you went into that depth. I guess it was to try to impress those who read this. I'm very impressed by the way. So are you now saying that yes a motor will run cooler with 220 vs. 120?

I'll take your word on it since you have listed your qualifications.

 

No, there will be no difference in motor temp. Maybe a slight difference in the temp of the wire going TO the motor, but that won't affect the motor one bit. A motor is going to be some percentage efficiency, typically in the 60-80% range on dual-voltage motors, the rest is lost to heat generated by friction and resistance. If the motor is 3 HP at the output shaft and 75% efficient, then the input would be the electrical equivalent of 4 HP (2984 W), which means the motor would draw 25A@120V or 12.5A@240V. But, because of what I explained above, the windings would always see 12.5A (or a fraction of that depending on how many windings the motor would have--if there were 4 windings, then each winding would only see 6.25A).

Jason

 

well yeah, but the 220v will still run smoother and somewhat cooler. Its an easy mistake to make, Ill diagram it below. while THERORETICALLY the series wiring will have twice the resistance, therefore half the current, same power, in practice the excessive line voltage drop due to the high starting and run current will cause it to run significantly slower, so the apparent load is higher.

this is greatly exacerbated if the motor is a single phase induction motor.

btw, you know this, power is lost according to I^^2*R (thats I squared times R)

consider a motor that runs on 120V, and has 2 20ohm coils. they are in parallel so what resistance does the line see? 20*20/(20+20) = 400/40 = 10ohms = 12amps. sounds about right?

Now rewire such that hot=t1, t2=t3, t4 = hot phased (std 240v wiring)

now the coils present 40 ohms to 240v, = 6 amps. 144 times ten is 1440 watts on the first shot, 36 times 40 is magically 1440 so we have the same rated motor assuming it was plugged into the power plant.

but it aint. power will be wasted in the line proportional to I^2. seeing as 12 wire will be the branch feed to the recep in either case, the power loss will be 4 times larger (some say 144 is 4 times as large as 36). power consumed in the line aint power consumed in the motor, hence peak operating rpm is not hit. (remember: the EMF which produces torque and rpms and things like that, is dependant on the current consumed in the MOTOR, not the line!) if this is a single phase indiction motor like a circ saw, a 200ft contractors extension cord can cause the motor to dang near burn up free running, let alone biting wood

this is why the manuals for high current motors want you to be as close to the box as possible, for most homes this is in the basement (just the place you want to go when the power is out - all the evil chuckles and scurrying noises) and is now generally specced in a utility room off the main floor. hence this run is going to be long. and arduous. and 220v makes more sense. (or we need to stop putting compressors in the garage and perhaps locate them next to the big screen plasma in the living room)

and dont worry about quals. everyone gots them. but they never alter reality. I did my EE at CMU but dang, that was 20+ some years ago, aint really used it since unless you count restoring vintage stereos. I joke that I could not spot you the thevenin equivalent of a toaster. (old sparky joke, I made up another one: write "jwL = 0" on paper and put that on a door. (get it? no admittance? cmon, its funny)

 

Moved to Garage and Workshop forum.