Unknown Compressor Make

[Roadkng]

Just got this compressor, and was unable to know it's identity, The Tank reads National Board Roy E Roth Co.No7783 m81 no 61-rr-5280 Year Built 1961

 

[RodneyW]

Welcome RoadKng. A picture will go a long way toward identifying the make of the pump. Roy E. Roth Co. is either the maker of the tank or the assembler of the complete compressor.
Rodney

 

[Roadkng]

Thanks, was able to post a picture, what do you think?

 

[RodneyW]

The picture isn't showing.
EDIT: Found it in the other thread and added it here.
I don't know much about compressors but I'm sure others here do.
Rodney

 

[Roadkng]

I hope someone could identify what Model Compressor this is, also how many Gallon tank.

 

[TRWham]

Small, single stage, 2 cylinder recip with 1.5 hp, 4 pole, dual voltage, TEFC, 145 frame motor. No idea who made the pump. Tank is probably 20-30 gallons, but you can calculate that from measurements.

 

[Roadkng]

Thanks TRWham, What would you estimate it's age?

 

[TRWham]

Tank says 1961. Motor may be a little newer. Not sure about pump.

 

[Roadkng]

Hi, Just got this old compressor running, took over 1/2 hr. to build pressure to 155psi. I guess the little V-twin pump is much too small for the 30 gal. tank. My question is what kind of pump would you recommend for the 1-1/2 hp. GE Motor that is on this compressor? I would like it to fill the tank in about 2min. Thanks

 

[454ragtop]

155 PSI is probably too high for that single stage compressor, consider lowering the setting on the pressure switch. Might be wrong, but I don't think filling that tank in 2 minutes with that motor is a very realistic goal.

 

[Roadkng]

Tried to lower the pressure down to 145psi, but still took forever to fill.. So you're telling me that not only do I have to replace the compressor pump, but have to change out the Motor too?

 

[Packard V8]

I don't think filling that tank in 2 minutes with that motor is a very realistic goal.

Tried to lower the pressure down to 145psi, but still took forever to fill.. So you're telling me that not only do I have to replace the compressor pump, but have to change out the Motor too?

Not at all. He's telling you to change out your expectations. There aren't any homeowner 1.5 hp compressors I've ever seen which will fill a 30-gallon tank to 155 PSI in two minutes.

I hope someone could identify what Model Compressor

From the appearance, it's a bitsa. The paint, piping and wiring indicate it being cobbled together from two or three different machines

FWIW, the GE Tri Clad is probably the best electric motor ever made.

jack vines

 

[Provincial]

120 psi is maximum for a single stage compressor. A more realistic cut-off pressure for an older unit like that is 100 psi. If it takes a long time to get to 100 psi, I would suspect that the pump needs work on the valves and/or piston rings. More problems with the valves unless it was run low on oil.

 

[Roadkng]

Thanks for all the info, so if I change the compressor pump to a larger one, what would you suggest to run on the GE Motor that is on there? By changing out the pump, wouldn't that decrease the running time to build up to Max. pressure?

 

[454ragtop]

A 1-1/2 HP motor can only turn so much compressor, you can't just grab the largest pump you can find and hook it up to that motor. There's a reason bigger compressors have bigger motors. I'm thinking you actually need/want a whole larger setup, tank, motor and pump. What exactly are you planning to use the compressor for?

 

[Roadkng]

Guess, I'll have to put this one up for sale, and look for something larger as you suggest. Too bad though, it's an old one, but hasn't been used much,and in great shape. I was planning on blowing out sprinkler lines in my yard, pool floats, tires, water lines to a Koi Pond, etc....

 

[RodneyW]

I would expect it to be fine for all those uses.

 

[454ragtop]

Why don't you try lowering the pressure switch to 100 PSI shut off and see how it works for what you want to do. Nothing you mentioned needs more pressure than that.

 

[TRWham]

You would need a 21 cfm compressor to go from 0 to 155 psig on a 30 gallon tank in 2 minutes, but you will not likely find a compressor that large mounted on a tank that small and it would probably have a 5 or 7.5 hp motor if you did. Not to mention that it would need to be a 2 stage to get to 155 psig reliably. A single stage compressor is typically limited to 130 or less, and lower is always easier for any compressor.

The compressor you have should be sufficient for everything you mentioned. Unless you just want a larger unit, set it to 120 psi cut-out and 90 psi cut-in and it will be fine.

 

[TRWham]

..
From the appearance, it's a bitsa...

I see what you did there . There really is a compressor (HVACR) manufacturer called Bitzer, but I don't think they have ever sold them as air compressors.