[Melrose RS]

My sears 1 hp compressor is starting really hard when it's cold outside. It draws enough current to trip a breaker on a power strip sometimes. But in the summer, no problem. I've never done any maintnance to it, other than drain the water out of the tank. Any thoughts on this?
Thanks.

[DOUG G]

Cold metal shrinks and different metals/thicknesses different amounts.

Now lets look at the motor tag or instruction book.... may require a separate 20 amp outlet (power strip isn't a good thing here).

[Melrose RS]

Originally Posted by DOUG G

Cold metal shrinks and different metals/thicknesses different amounts.

Now lets look at the motor tag or instruction book.... may require a separate 20 amp outlet (power strip isn't a good thing here).

Yes, it's definitly better without the power strip. I don't have an instruction book though. I got the compressor off a buddy many years ago. Would the compressor oil (or lack thereof) being old matter? Maybe I should check to see if there's any in there...

[Everett#2390]

Originally Posted by Melrose RS

Would the compressor oil (or lack thereof) being old matter? Maybe I should check to see if there's any in there...

Old oil becomes like sludge/molasses.

[Melrose RS]

Originally Posted by Everett#2390

Old oil becomes like sludge/molasses.

Thanks Everett. I better check it, then.

[Everett#2390]

You're welcome. If you do wire in a separate circuit, use #10 AWG, less current loss for the total run, more power for the motor.

[Sauron67MM]

Originally Posted by Everett#2390

You're welcome. If you do wire in a separate circuit, use #10 AWG, less current loss for the total run, more power for the motor.

Just do what Everett says. Or you'll keep tripping breakers. Insufficient juice is not good for an elecric motor. And you may even be on the end of a run. Ever see people running power tools with a Christmas light extension cord? Unbelievable.

[Melrose RS]

I've got one 20 amp circuit running to my detached 1 car garage. Mostly just runs the lights and tunes. Occasionally the compressor for the impact wrench. Just a little scary in the winter(or now) when it's cold out and the compressor labors to start.

[Sauron67MM]

Originally Posted by Melrose RS

I've got one 20 amp circuit running to my detached 1 car garage. Mostly just runs the lights and tunes. Occasionally the compressor for the impact wrench. Just a little scary in the winter(or now) when it's cold out and the compressor labors to start.

What size wire is running to garage? Is there a sub panel in the garage or are you just running off the panel from the house? Best to have lights, outlets and compressor on separate circuits.

[Melrose RS]

I think it's #12 AWG. No sub panel. Just one breaker in the house panel for the garage. Old house (1920's) but upgraded electricals.

[Everett#2390]

Do a power check, with a cold compressor, plug it in at the house and observe the starting characteristics.
Next day, with cold compressor, plug it in the garage and note symptoms.
If garage start-up is slower, then you need a larger gauge wiring to the garage.
Too much current loss between the house & garage.
You should have a subpanel in the garage for at least safety reasons.

[James Merriner]

Gooday mate, I'm sort of new to this forum (2 year member, but no posts until now) I'm from down under and I happen to repair compressors for a living, so heres my 2$ worth. You don't mention whether this is a new problem or she starts hard since new. If new, check the start up from a different power supply, as was stated in the last post. If she has only just begun the problem after a period of no problems, then it will not be the power supply, unless you started your compressor when everything in the house just happens to be on ( I have a similar problem at my place, pool pump on, compressor running will trip the breaker, but no hard start) Sounds like one of two problems, maybe three. First thing to do is check the unloader, a small check valve under the pressure switch, this unloads the head pressure at stop, you will have heard the familiar blast of air each time your comp. reaches your upper pressure setting, if this was ok prior to the starting problem then check the motor capacitor, just look for visual problems, split casing, black/brown marks on casing. Easy to replace and cheap, about 20 to 30 dollars here. Careful though, as they store a charge, touching the terminals could give a bit of a zap, and if you have a heart condition well... hold a screwdriver across the terminals and the charge will go. Third problem could be a faulty motor, but fairly unlikely in my experience. Also check the freeness of the pump, should turn with little effort. It just sounds like its starting under load, so I would check that unloader valve, try to start it with the line removed, either nylon or copper. I hope I havn't tried to reinvent the wheel here, and you have probably checked all of these things anyway, but if I have been of any help... cheers, love Camaros

[Melrose RS]

Originally Posted by James Merriner

Gooday mate, I'm sort of new to this forum (2 year member, but no posts until now) I'm from down under and I happen to repair compressors for a living, so heres my 2$ worth. You don't mention whether this is a new problem or she starts hard since new. If new, check the start up from a different power supply, as was stated in the last post. If she has only just begun the problem after a period of no problems, then it will not be the power supply, unless you started your compressor when everything in the house just happens to be on ( I have a similar problem at my place, pool pump on, compressor running will trip the breaker, but no hard start) Sounds like one of two problems, maybe three. First thing to do is check the unloader, a small check valve under the pressure switch, this unloads the head pressure at stop, you will have heard the familiar blast of air each time your comp. reaches your upper pressure setting, if this was ok prior to the starting problem then check the motor capacitor, just look for visual problems, split casing, black/brown marks on casing. Easy to replace and cheap, about 20 to 30 dollars here. Careful though, as they store a charge, touching the terminals could give a bit of a zap, and if you have a heart condition well... hold a screwdriver across the terminals and the charge will go. Third problem could be a faulty motor, but fairly unlikely in my experience. Also check the freeness of the pump, should turn with little effort. It just sounds like its starting under load, so I would check that unloader valve, try to start it with the line removed, either nylon or copper. I hope I havn't tried to reinvent the wheel here, and you have probably checked all of these things anyway, but if I have been of any help... cheers, love Camaros

James, thank you for your advice. All I've done since posting this thread is try the compressor directly off the garage wall circuit with no power strip in line and that improved things 98%. I still haven't checked the oil, maybe today.

[James Merriner]

Hi guys, in response to some of the compressor problems that can occur, I thought I would share a couple with you. As mentioned, I work as an Industrial Compressor service tech for a company called Champion Compressors in Aussie. No, we are not affiliated with your Champion line, and from some of the things I have read in various posts on this site, I am probably happy about that. We are actually owned by Sullair, one of your biggest and best ( in my opinion) brands out there.As stated ,I only do industrial stuff, but do come across the odd single phase unit, plus I had a part time job at a hardware chain similar to your Home Depot, in fact almost an exact copy! So here go's, guy brought back a new direct drive unit complaining that it would not start. He had arrived home, set up his new compressor, then heard a strange air leak every time the comp. stopped, so he pulled the offending tube out and plugged it. No leak now, although she started hard every now and then, until she would not start at all, one burnt motor to brighten his weekend and a 30 min. explanation on what he did wrong, plus no warranty to boot. Guys who will buy three extension leads ( 10 amp ) and only 10 metres of hose so they can use the comp. right next to the job. Very bad for the motor. Oil levels right up to the oil filler plug! whats that little clear window for? One cust. complained that his unit stopped and started every 15 sec. or so, ran just a short time and stopped, only to repeat the cycle again and again. receiver was full of water, drain the tank!99$ special 2 HP units that people want to run sandblasters and air tools off of, no way. Buy the very biggest air comp. that you can afford/get away with ie. noise problems etc. even if you have to upgrade your workshop electricals, like I am going to do shortly, as I have plenty of compressors to run all my gear, but not enough power. On that note, can one of you guys explain to me the difference in your power supplies? You run 110V and 220V supplies, I am assuming that 220V is also single phase, am I correct? We have 240V single phase and 415V 3 phase and that is it, unless certain companys have higher voltage supplies for various uses, cheers, James

[Lyin Lyle]

Melrose. That compressor problem is not new. I have fought it in race trailers and in homes. Best I can tell is you are trying to run it on 115volts. If so the dedicated circut will make a big change and as short of run from panel to motor. The next best and what I would do. Is put in the sub panel and use it on 220 volts.Its just like adding a big carb and pump but a small line to the pump from the tank will drop it to its knees .Almost all of these motors just take some moving of the wires and have the diagram inside. Like everyone has said. It will ruin the motor. If it starts hard it may be working when it gets up to cut of psi also. Best of Luck LL