Milton Regulator not releasing pressure

[Beaupr]

I have a Milton filter and 1/2" npt regulator near the compressor and from there the lines are plumbed to the rest of the shop.

At the end of one of the drops I have another filter and regulator (same ones as by the Compressor)

When I drain the tank and lines, the regulator at the end doesn't release or drain the air, it just stays at the set pressure.

If I open the valve at the end of the piping, then it drops to zero immediately.

Is this normal? When the pressure is full I can adjust it and it moves up and down properly.

Thanks

 

[johnre]

Yes, at least for mine.

It makes it hard to know where your pressure is set when you're dropping the pressure at the regulator; I need to first add an air accessory to waste some pressure on the regulated side.

 

[vanapplebomb]

for most regulators, this is the case. For specific applications you can buy exhausting regulators that bleed pressure when you back them off… but it’s not your every day thing. They are a bit more expensive than a normal regulator, but not too bad.

 

[The Cobbler]

your regulator is non bleeding. means that as the pressure is reduced by turning the knob , it bleeds off the excess pressure . your's down;t do that. In my experience, most regulators are bleeding type.

 

[Beaupr]

your regulator is non bleeding. means that as the pressure is reduced by turning the knob , it bleeds off the excess pressure . your's down;t do that. In my experience, most regulators are bleeding type.

Thanks for your reply but (unless I'm wrong) I believe it is a bleeding type. It's a Milton 1115-8 and a description I found says "1/2" NPT high pressure regulator is the heavy duty relieving type"

Assuming bleeding and relieving type are the same. There is a 1/8" hole on the side that air comes out when I adjust the pressure. This just seems to happen when the lines are drained completely.

It's brand new so maybe I should exchange/return it. Just don't feel like taking the piping apart

 

[The Cobbler]

"1/2" NPT high pressure regulator is the heavy duty relieving type"

yes, I would agree that it's supposed to be a bleeding type.
not sure what to say. You do have it oriented the right direction I assume/.
it could be defective

 

[Jack Ryan]

I wonder if all self relieving regulators will bleed to empty if the source pressure drops. It will bleed if the output pressure is greater than the set pressure - if that is based on spring pressure, it won't bleed.

Jack

 

[5ubtle]

Is this normal?

I don't have a similar piping, so I can't test it, but I believe that @johnre is correct.

Your Milton 1115 seems to be similar to my Speedaire which is similar to the regulator described in Patent US3282285.

The 'bleeding' functionality is described as:

"The upper end 78 of the stem is enlarged and spherically shaped terminally to close in sealing contact with a valve seat washer 82 disposed in a recess 80 whereby a safety pressure relief valve port 84 vented to atmosphere is provided out through the bonnet 30. Thereby, Whenever the lock-up pressure or pressure present in the outlet conduit 14 is too high, the diaphragm 28 is raised thereby to clear the upper end 78 of the pin 46 and air escapes through passage 84 to relieve the excess pressure. Thereupon, the diaphragm 28 returns to and closes the washer 82 against the head 78 to close the passage 84."

The key is to realize that the diaphragm is balanced by 1) the spring pressure controlled by the adjustment knob, and 2) the regulator outlet pressure. The regulator inlet pressure does not effect the diaphragm.

This design will result in exactly the behavior you describe.