15 amp too much draw for small compressor?

[CarLuver]

i picked up one of these off the side of the road. took it home and it did 2 things. it did not pump which i tracked to a bad unloader valve. $5 amazon part fixed that. 2 it would pop the 15amp circuit breaker when pumping up. i decided to bypass the breaker and then checked the amp draw with my meter. it drew around 15.5 amps.

So do these small compressor draw this much amperage normally? after bypassing the breaker it works as it should and pumps up quickly.

https://www.harborfreight.com/air-t...hp-125-psi-oil-lube-air-compressor-62441.html

 

[ctechbob]

Might want to check the motor start capacitor. I have the big brother to that one with what looks like the same/similar pump, it will pop the power strip breaker if it runs a long long time.

Also might want to change to a thinner oil. The oil HF provides is pretty thick and hard to start sometimes, especially cold.

 

[blufeb95]

2.5HP*750W/HP=1875W
1875W/120=~15.6A
So yes, it has a 2.5HP motor it should draw around that much.

 

[Dennywires]

i would check the capacitor as mentioned. running amps should be lower. as stated in the manual a 3 prong receptacle rated up to 125v and 15 amp. the manual says running amps are 14 amps and a dedicated circuit is recommended.

 

[atikovi]

i decided to bypass the breaker

That doesn't sound very safe. You must have some 20 amp circuits around the house that you could plug it into. Oh, that 2.5 HP is just marketing hype. I have a 60 gallon tank compressor and it says 7 HP, but down in small letters, it mentions 2.9 HP. That runs from a 220V outlet.

 

[mk378]

Nice find. That unit has pretty good air output but like any compressor it will use a lot of current.

For an induction motor, lower voltage at the motor means more amps and heat. Plug directly into the wall, ideally on a 20 amp circuit with a short run of #12 wire to the breaker box. Do not use power strips or extension cords. If the job is farther from the outlet, buy an air hose.

 

[oggb]

I have the bigger version of that in one of the shops and as loud as that mfer is it better be drawing AT LEAST 15 amps. I have it in a 20 amp breaker and it hasn't ever tripped it even during heavy use.

Maybe make sure it actually has oil in it and/or change the oil. Like @ctechbob said the oil they come with is very thick. It's thicker than any compressor oil I've ever run and when it was very cold I could hear it laboring to start.

 

[CarLuver]

That doesn't sound very safe. You must have some 20 amp circuits around the house that you could plug it into. Oh, that 2.5 HP is just marketing hype. I have a 60 gallon tank compressor and it says 7 HP, but down in small letters, it mentions 2.9 HP. That runs from a 220V outlet.

perhaps i should have been more clear. there is a circuit breaker on the compressor rated at 15 amp and that is what i bypassed, not the home circuit. it does not trip the 15 amp home breaker.

i think the compressor one has been tripped so many times it has worn out. i will get a new one from amazon .

 

[CarLuver]

Might want to check the motor start capacitor. I have the big brother to that one with what looks like the same/similar pump, it will pop the power strip breaker if it runs a long long time.

Also might want to change to a thinner oil. The oil HF provides is pretty thick and hard to start sometimes, especially cold.

i beleive this is one of the dual run types. i checked it with my meter and its in spec. i am going to change the oil and see what happens

 

[ctechbob]

I currently have Havoline 5W30 in mine. The HF oil was so thick I couldn't get the compressor to start when the temps dropped below about 50 degrees.

 

[Dennywires]

I’ve always used non detergent 30wt in compressor maintenance and the newer compressors I worked on use a synthetic that didn’t have a wt listed. I have also seen some manuals list Mobil 1 10w30 full synthetic suitable for use. Usually on the kobalt compressors.

 

[#18FAN]

I currently have Havoline 5W30 in mine. The HF oil was so thick I couldn't get the compressor to start when the temps dropped below about 50 degrees.

Agree that Factory fill oil drains like peanut butter.

 

[Fitter30]

Not knowing your exact model number on HF site one that looks like the pic 14 amps

 

[Dennywires]

Agree that Factory fill oil drains like peanut butter.

What do you think that factory oil is?

 

[spackard]

Before you put too much into it - I once borrowed with intent to buy a unit from a coworker/scavenger. I used it for a half-hour and all the oil pumped from the sump to the tank. (I declined the purchase.)

 

[CarLuver]

changed the oil today. i put in some 5w30 i have laying around. started it and checked the amp draw. draw is still 14.5 . pretty surprised at how quick it pumped up to 120psi compared to my 30 gal. i guess 15 amps seems to be normal for these things.

 

[ctechbob]

What do you think that factory oil is?

Being HF, probably whatever they could get cheap. Some kind of single weight mineral oil I would suppose.

 

[ZeeOSix]

Running a full synthetic ISO 68 compressor oil in my Craftsman. ISO 68 is 68 cSt at 40C, and basically the same KV100 as a heavy 20 weight.

 

[blufeb95]

Running a full synthetic ISO 64 compressor oil in my Craftsman. ISO 64 is 64 cSt at 40C, and basically the same KV100 as a heavy 20 weight.

I'd say that's more along the lines of an ILSAC/Resource Conserving Xw30.

 

[ZeeOSix]

I'd say that's more along the lines of an ILSAC/Resource Conserving Xw30.

It's the only thing I run a "20 weight" in. It's not multi-weight, and non detergent, as the Craftsman manual recommends.

Viscosity Chart - ISO 68 is a heavy 20 weight.