New Compressor

[JaxGarage]

Just purchased a new CH 20gal oil filled compressor. It runs nice and smooth and quiet until it builds 50 psi. From there on it seems to have a knock. Is this normal to have the knock as the pressure builds? It builds pressure without any problems but was just concerned with the knocking noise.

 

[pattenp]

That doesn't sound good to me. I have a 18 gal comp and it sounds the same from start to stop, no knocks as pressure increases. If it's new why not take it back to where you purchased it and get a new one.

 

[JaxGarage]

Listened to my buddies compressor and it does the same thing but his is five years old and he can't remember if it did it from new.

 

[larry_g]

You may have to go to a higher octane air to get rid of the knock

lg
no neat sig line

 

[JaxGarage]

Now thats funny.
The thing is, I live 45min from where I bought it and don't want to return if this is normal. My dad has same compressor and his also has the same knock. Does nobody else have a CH compressor that can verify if I need to return.

 

[mryyc]

I have an older CH Professional 20 Gallon with the horizontal tank. I bought it second hand, it's dated I think 1995. I've never noticed a knock, did you purchase it new?

 

[Bob C]

Just purchased a new CH 20gal oil filled compressor. It runs nice and smooth and quiet until it builds 50 psi. From there on it seems to have a knock. Is this normal to have the knock as the pressure builds? It builds pressure without any problems but was just concerned with the knocking noise.

YES. It is normal. The sound you hear is the ringback of the checkvalve.

 

[79firebird]

I had the same pro with a 80 gal. the screw for the fly wheel on the compressor head just wasent tight enuf. 1/4 turn and its been good.

 

[JaxGarage]

Thanks for the info everyone. I've heard a couple more of these compressors running and they all do the same thing so I guess all is good.