Pressure regulator / Relief valve

[tomtucson]

Not exactly sure what they are. I would like to use a regulator or relief valve (same thing?) instead of an unloader so it can be plumbed 'off line', allowing the water to go straight from the pump to the gun. Am I correct that when the gun is off the water will be full flow, full pressure - meaning the engine is working full out when you are not spraying? I was thinking it could work with a clutch or kick-down for normal flatwork. Thanks

 

["Red"]

Flow unloaders don't work that way from what I understand, pressure unloaders do.

 

[Pat Norman]

Not sure what you are talking about. With either type of unloader once you let off the trigger gun it goes in bypass through a 3/8 or larger hose. So even though it's still pumping same amount of water it's not going through a high pressure nozzle so it's not working hard at all. I know there are some clutch configuration s for pumps out there but just seems more complex and maintenance.

 

[Russ Johnson]

Yes Tom. A regulator is going to maintain the pressure on the pump holding the valve open.

 

[tomtucson]

What I am talking about is not an unloader, pressure or flow. It's kind of like having your unloader on a tee to the side - so when you're spraying the water goes straight to the gun, not through the 'unloader'. When you shut off the gun the water goes through the tee over to the 'unloader'. Pressure relief valve, very simple, few parts and cheap.

 

[pdmcali]

I am curious what is the benefit?

 

[tomtucson]

I am curious what is the benefit?

Free Flow - the water goes through full sized plumbing and not through the small passages in the unloader.

 

[Pat Norman]

I understand now. This sounds interesting. I wonder if there is a way to use an unloader plumbed to the side this way? Seems like it could be. Just plug the high pressure outlet and run the bypass outlet to the buffer tank as normal. Hmm don't know. That's probably too not right.

 

["Red"]

Free Flow - the water goes through full sized plumbing and not through the small passages in the unloader.

Is the "full sized plumbing" capable of handling 3-4000psi?

 

[Pat Norman]

Is the "full sized plumbing" capable of handling 3-4000psi?

That would be pressure rated jumper hoses I guess. The tee's etc can handle it too.

 

[tomtucson]

I understand now. This sounds interesting. I wonder if there is a way to use an unloader plumbed to the side this way? Seems like it could be. Just plug the high pressure outlet and run the bypass outlet to the buffer tank as normal. Hmm don't know. That's probably too not right.

Not an unloader, but that is what these regulator/relief valves are for. The catch is the engine and pump work at full pressure when NOT spraying.

 

[Pat Norman]

Okay I see. So when you let off the spray gun the "relief valve" sends the water back to the buffer tank but it has to be set to hold full pressure so that it will send water back to the spray gun when it is open and at full pressure.