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3/4 NPT air?

ngng

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Need to hook up my new air supply too the existing air compressor tank. Output is 3/4 NPT but the existing tank is 1/2 NPT. I know the line itself isn't 3/4 or 1/2 itself. If the tank itself is 1/2, is it dumb to run a 3/4 to 1/2 adapter and then just run 1/2 NPT whips?
 
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ngng

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Whops, hit post too quickly. I've also seen recommendations for the Rapid Air MaxLine.
 

u2slow

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I would probably adapt it directly with a NPT bushing/reducer. Pay attention to the inner diameters for possible flow restrictions.

Keep in mind that nearly any connection to an air fitting or hose loses one nominal size.
 
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ngng

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I would probably adapt it directly with a NPT bushing/reducer. Pay attention to the inner diameters for possible flow restrictions.

Keep in mind that nearly any connection to an air fitting or hose loses one nominal size.

I probably need to get a larger tank with a 3/4 inlet at some point heh
 
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ngng

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It won't matter unless your air draw is massive.

A single fitting doesn't reduce the whole system down to that size.

Ideally I would supply air through 3/8, but that line is currently pulling from a 1/2" reducer as well. Everything is OK. I could also just not worry about all of this and run a smaller surge tank that has a 3/8 fitting and supply with 1/2.
 

GeoBruin

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Need to hook up my new air supply too the existing air compressor tank. Output is 3/4 NPT but the existing tank is 1/2 NPT. I know the line itself isn't 3/4 or 1/2 itself. If the tank itself is 1/2, is it dumb to run a 3/4 to 1/2 adapter and then just run 1/2 NPT whips?
Sorry, I'm confused. Are you talking about a pump and the hard line that goes into the tank from the pump outlet? What do mean by air supply?
 
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ngng

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Sorry, I'm confused. Are you talking about a pump and the hard line that goes into the tank from the pump outlet?WWhat do you

Sorry, word vomit. Was looking at too many notes :)

The largest ID air line is 1/2" ID and it runs fine off the 1/2" NPT air tank output. The new compressor and dryer is 3/4" out. I think if I use a 3/4" NPT to 1/2" NPT reducer everything will run just fine.
 

GeoBruin

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Sorry, word vomit. Was looking at too many notes :)

The largest ID air line is 1/2" ID and it runs fine off the 1/2" NPT air tank output. The new compressor and dryer is 3/4" out. I think if I use a 3/4" NPT to 1/2" NPT reducer everything will run just fine.
Got it. And you are correct. A 3/4" to 1/2" bushing in the tank bung is the way to go.

Also, 3/4" Rapid Air Maxline uses 1/2" NPT fittings.
 
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ngng

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Don't really want to buy a new tank right now so I was thinking of just plumbing directly into the old air compressor. It doesn't make sense to add a T to the output does it? I looked under the compressor housing and there's a 1/2" NPT inlet but it's kind of hard to get access to.

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GeoBruin

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Don't really want to buy a new tank right now so I was thinking of just plumbing directly into the old air compressor. It doesn't make sense to add a T to the output does it? I looked under the compressor housing and there's a 1/2" NPT inlet but it's kind of hard to get access to.

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Wait, now I'm even more confused. There are two compressors? Which one are we looking at?
 
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ngng

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Wait, now I'm even more confused. There are two compressors? Which one are we looking at?

That's my old compressor. I want to plumb my new air compressor to use the existing tank. I guess it's be nice to also have a backup?
 

GeoBruin

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That's my old compressor. I want to plumb my new air compressor to use the existing tank. I guess it's be nice to also have a backup?
So does your new compressor have a tank? Or it's just a motor and a pump?
 

GeoBruin

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I have a compressor and dryer, no tank. The plan was to run new compressor => AC => old compressor tank
I guess the obvious question is why don't you just mount the new pump on the old tank? Unless you want to run both compressors for more flow. In which case, ideally you find a way to plumb the output from the new pump into the tank.

How are you handling a pressure switch on the new setup? What shuts it off?
 
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ngng

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I guess the obvious question is why don't you just mount the new pump on the old tank? Unless you want to run both compressors for more flow. In which case, ideally you find a way to plumb the output from the new pump into the tank.

How are you handling a pressure switch on the new setup? What shuts it off?

Heh, I would if I could but the new compressor and AC are stand alone. Realistically, I probably don't need a "back up". Maybe just makes sense to add a 1/2" elbow to the top of the tank and plumb directly into it. Then, if I buy a new tank I can hook it back up and sell the whole thing.
 

GeoBruin

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Heh, I would if I could but the new compressor and AC are stand alone. Realistically, I probably don't need a "back up". Maybe just makes sense to add a 1/2" elbow to the top of the tank and plumb directly into it. Then, if I buy a new tank I can hook it back up and sell the whole thing.
That would be ideal but I still don't know how you're going to signal the motor to stop based on a tank pressure without wiring the new motor to the pressure switch on your old tank. Unless you've got some kind of tankless, continuous setup with a pilot unloader valve or something but you have been very vague about that part of the setup (no description, no pictures, etc.) so we're all just guessing here.
 
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ngng

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That would be ideal but I still don't know how you're going to signal the motor to stop based on a tank pressure without wiring the new motor to the pressure switch on your old tank. Unless you've got some kind of tankless, continuous setup with a pilot unloader valve or something but you have been very vague about that part of the setup (no description, no pictures, etc.) so we're all just guessing here.

Sorry, here you go.

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GeoBruin

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We'll that's certainly a badass compressor and probably could run continuously but I'm sure you don't want it to. How do you plan to shut it off when the tank is full?
 
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ngng

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We'll that's certainly a badass compressor and probably could run continuously but I'm sure you don't want it to. How do you plan to shut it off when the tank is full?

Thanks, I hope it works out. Every time the IR kicks on I get so annoyed. Hoping the replacement will let me think in peace! I think it's got a built in pressure sensor, but..I'm not 100% sure.
 
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ngng

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Got everything wired and working. Took me about a day to figure out the 3 phase and get all the adapters. Need to pick up an elbow so the compressor output isn't pointed straight out. Lots of little things to do, but at least I have air again!

Regarding the shut off, it cuts off at 125psi and kicks back on around 100 psi.

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