Question about Northern Industrial 2 Hp Twin Tank Electric Air Compressor

1 Answer

Starting the unit

My compressor (a portable) starts pumping when I turn it on. It goes up to 120 lbs and then at the point it is to shut off, it does. The air then starts escaping from the compressor switch and purges the tank down to 70 lbs; I believe that this is through the unloader which is built into the pressure switch. The compressor tries start up again, but fails and repeats this action until I shut the system down by pulling the plug because if I try to depress the on and off switch it lets more air out of the tanks. The pressure switch was replaced with a new one, but this did absolutely no good, it keeps doing the same thing.

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert that got 5 achievements.


    An expert who has written 20 answers of more than 400 characters.


    An expert who has answered 20 questions.

  • Contributor
  • 65 Answers

I am thinking it is 110 volt. the reason I mention that is because I had a similar problem with powering back on but without the air leakage. Narrowed it down to insufficient power supply. As it didn't do it all the time. And I think the built in thermo protector somehow had an effect. Think the motor heated up faster due to not enough current, and the thermo protection tried to keep it from starting but wasn't working properly to start with I don't think after it was a year or so old. It drew 15 amps, That is a big draw. Turn on a skill saw at the same time there went the breaker. Different locations it acted differently.

In your case I think if you replace that entire power switch pressure unloader assembly. It sounds like at least your describing an assembly, that definately sounds faulty and may be the root of the whole problem. Then just to check, check your amp draw for the compressor and make sure the circuit your plugged into doesn't have a lot of other demands. Better to get 25 feet more of air hose then use an extension cord, depending on your amps for your compressor.
The way it's described sounds like the on off switch, pressure switch that controls the auto on and off, and the pressure relief/unloader valve are all together. So when you say you replaced the pressure switch, did you replace the whole assembly ? If I am calling that correctly in picturing it as being one combined unit ?


Posted on Nov 20, 2008

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

I have a D55168 Dewalt compressor. Since I've had it, it has never shut off automatically and I've always shut it off manually at 200 psi. If I leave it alone, will it automatically shut itself...

Your concern is very well placed, at pressures that high a lot of damage can be caused by a failure. According to the manual for this model air compressor the approximate cut-in pressure is 160 psi and the approximate cut-out pressure is 200 psi. Meaning it should pump up to 'about' 200 psi and shut off and not come on again until it gets down to 'about' 160 psi. They say approximate and I say about because it's not an exact science setting the pressure switch. Spring rates are not always exact, pressure guages are not that precise, etc. When turned on, it should shut off at 200 psi +/- 10 lbs. If it goes more than 10 lbs over that (220psi), I'd recommend you get the pressure switch and or guages checked or replaced.

Jun 16, 2011 | Dewalt D55168 1.8 HP Wheeled Portable...

3 Answers


If the pump is putting out 40 lbs then it is working these things are loud there must be air leaking out some where are you sure that the petcok on the bottom of the tank is closed or the blow out valve is not leaking or mabey I would say the gauge but it dosn;t shut off If the pump is putting air in that tank it eigther compresses or it comes out run your hands all around the mechine when its running there must be a leak

Nov 24, 2010 | Campbell Hausfeld 2 Gallon Air Compressor

1 Answer

I have a 5 gal, i hp craftsmen compressor, 3 years old, used once a year to blow down sprinkler system. Compressor ran up to 120 lbs upon turn on, would not cycle off. manually shut off unit and turned...

Oil free pumps do tend to blow the piston ring (not too expensive) available at Remove covers to pump and manually turn crank until piston is at top and look at the condition of the cylinder neer top, If it looks scratched, order cylinder kit with piston ring. If it looks good and shiney, could be the valve plate in the head. There are reed valves that tend to break. Run pump however with covers removed and check with soapy water for air leaks and repair as needed (air leaks under the cover will prevent unit from filling). Good luck

Nov 13, 2010 | Craftsman 15 gal Air Compressor 3 hp UMC...

1 Answer

After starting the compressor, the tank does not fill up to 120 psi and shut the compressor off automatically. It will continue to run and not fill the tank completelhy. How can I fix this?

It could be one of three things. 1. The air intake could be dirty to the point that it cannot take in enough air volume with each cylinder stroke to be able compress it to 120. Try cleaning the air filter. 2. The reed valve that prevents the return of air from the tank to the compressor is not sealing well. This might be cleanable, but requires disassembly. 3. The cylinder itself has a poor seal giving you bad compression. This would require major surgery and parts, and is probably not worth fixing.

Jun 29, 2010 | Campbell Hausfeld FP2080 4 Gallon Portable...

1 Answer

2 hp 120 v motor on compressor. motor will not start under load

bleeder valve is bad or dirty drain air unplug machine pull the back up plate control plate and make it shinny with emmeory cloth then clen it and try again, if it still does the same thing your going to nedd to replace unloader valve.

Apr 14, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

Small Sears compressor will not shut off

could be a piston ring problem blown gasket sticking valves what did you over haul get back to me

Sep 20, 2009 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

Craftsman 3 gal ari compressor low presure

put a blower on the hose and see if air comes out
very possible there is a blockage in the hose or if you are using quick connects they may have failed

Apr 17, 2009 | Craftsman 3 gal. Air Compressor, 1.5 hp,...

1 Answer

Leaks air at the pressure switch

start your compressor and let it buid up pressure to turn off. then unplug from power.lossen the fill tube that goes from the pump to the tank. when you loosen it. if it leaks air then your check valve is bad and will have to be replaced.

Dec 25, 2008 | Craftsman 3 gal. Air Compressor, 1.5 hp,...

1 Answer

Cycling compressor

The pressure switch will shut off when the set pressure is obtained. Usually about 100 to 120 lbs. If the compressor stops at lower pressure than mentioned you may try to adjust the pressure by looking under the switch cover for adjustment screw/nut.(no more than a few turns) Increase pressure by increasing spring tension. Quick cycling is usually caused by air leaking from tubing, drain valve or check valve. After compressor shuts off unplug it from the outlet and spray soapy water on all fittings and drain valve. Repair leaks and test for quick cycling, however the compressor should reach 100-120 before shutting off. Some small compressors have a thermal reset but that usually takes a few minutes to reset. Pressure switch is defective if it shuts off before setting mentioned. Enjoy

Dec 11, 2008 | Craftsman 3 gal. Air Compressor, 1.5 hp,...

Not finding what you are looking for?
Northern Industrial 2 Hp Twin Tank Electric Air Compressor Logo

123 people viewed this question

Ask a Question

Usually answered in minutes!

Top Northern Industrial Air & Gas Compressors Experts

John Trevino

Level 3 Expert

1378 Answers


Level 3 Expert

2386 Answers


Level 3 Expert

61037 Answers

Are you a Northern Industrial Air and Gas Compressor Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides