# Reverse Regulator?? Depressurizing Regulator??



## Jwrigh12 (Dec 5, 2021)

Hi everyone! I hope youre doing well! 

I have a bit of a strange question, and Im hoping that the Power Equipment gurus can provide me with some wisdom! 

I have a system that needs to be regularly pressurized and depressurized... but to varying psi ratings. Pressurizing the system is simple! Line from the compressor, slap on a regulator, and the compressor will never feed more pressure than the regulator is set at! Pretty much set and forget, and I can set the pressure to different a different PSI depending on the requirements. 

Where Im stuck is the depressurization... 

You'll have to forgive me if this is a forum post somewhere else... I dont even know what the appropriate search terms would be.

How can I set up a "depressurizing regulator"? The goal is to set the desired PSI on the "regulator", then open a ball valve. When the system pressure reaches the appropriate PSI, the system stops bleeding pressure. 

Kinda stuck here. I would prefer to have this be a system that I can set and walk away from, rather than do the "bleed, check, bleed, check, etc..." thing. 

Any help you can provide would be most helpful!! Thanks so much!


----------



## iowagold (Jan 22, 2020)

so what is the exact application?
how many stations or work areas?

you want to select the single compressor by the largest pressure and largest cfm needed.

there are several ways to do this depending on cfm required and pressure.

you can go a multi tank multi regulator setup. and multi ports for each output.

or if this is for single station use.
you can go electric valves to many regulators to select the pressure for the station.

all of this can be set up with 120 vac valves, relays and a single control electric selection knob.


----------



## Jwrigh12 (Dec 5, 2021)

So, I have the compressor setup figured out, along with pressurizing the system to its high pressure limit. What Im trying to figure out is how to RELEASE pressure from the system, down to a specific PSI. The compressor would not be involved at that point, as this is a pressure release... or so my thought goes. 

As far as the actual application... let me first preface this by saying that I have often found that the industrial world lends itself to providing solutions for the everyday user! 

I am working on an overland rig's on board air, 4 wheel pressure system. The system so far is: Two Smitty built air compressors feeding a 3 gallon air tank. this tank feeds several systems on board the vehicle. One of which is this 4 wheel pressure system. When hitting the trail, the tire pressure needs to be lowered to 15-20 PSI (for greater contact area and traction), and when returning to the pavement, the tires need to be aired back up to 35-40 PSI again. 

Airing back up is simple. the main feed line is connected to the air tank with a regulator in line. The desired pressure is set, and the compressors are turned on. Once the desired PSI is hit, the regulator shuts off the flow. 

Airing down the tires is the issue. I'm looking for a way to (much like airing up) set a "regulator" of sorts to the low pressure level I desire, then open a ball valve. Once the low pressure is reached, the flow is shut off, holding the tires at the desired pressure.


----------



## iowagold (Jan 22, 2020)

so are you changing pressure on tires or an air ride system on this RV?
what is the total weight on the RV?

dump of pressure is easy.
electric valve and set pressure sensor as a stop point.
you can have multi settings on the dump.

or a simple multi tank setup if you are looking at 2 pressures.
just switch tank systems.

and make sure to use a snuber or silencer for the air dump.

3 gallon tank is way way too small. 

you might want to see out an low rider forum.
they do radical pressure up and dump on on pneumatic systems..


----------



## Jwrigh12 (Dec 5, 2021)

So, its not an RV or an air ride system. Its a Tundra built into an off road/overland rig. As for the air system, a three gallon tank is actually overkill. Many people who use systems like this use a single mini compressor. It takes a while, but works as designed. Im using two compressors and a buffer tank. That part of the system Im not concerned with. Its already designed and proven. 

Can you tell me more about the electric valve and pressure sensor that you were talking about?


----------



## iowagold (Jan 22, 2020)

check this site
*https://www.ridetech.com/product-category/products/air_suspension/air-ride-suspension-control-systems/*

so are you changing pressure on tires or an air ride system on this off road unit?
what is the total weight loaded on the unit?
and what is the cfm and line inside diameter required?
and what is the psi required?


----------



## Jwrigh12 (Dec 5, 2021)

I am simply changing tire pressure. Nothing to do with ride height. 

Weight is TBD as the build is continuing... but does not actually matter in this use case. CFM is about 11 through a 3/8 line. And tire pressure was stated above. Down to 15PSI up to 40


----------



## Jwrigh12 (Dec 5, 2021)

Quite honestly Paul, I appreciate the responses. Thank you for your time. However, Im really just looking to solve the question I asked. I know the system I want to install, and what its capabilities are. 
Im simply looking for a way to automatically close a discharge line when a low pressure point is reached. Im not trying to redesign a system that is already proven. 

No disrespect meant... just want to make sure we are on the same page


----------



## iowagold (Jan 22, 2020)

is this 12 volt dc or 24 volt dc?
how many cf are each tire and how many tires?
how fast do you need the change in pressure?


----------



## iowagold (Jan 22, 2020)

so basic do a valve on the compressor tan out to the system, and an inline T with a valve for the dump.
you can use ball valves or electric valves.
and do a large guage on the dash for the pressure.

are you looking for a full manual control system ?
or a flick of the switch for 2 tire pressure settings?


----------



## iowagold (Jan 22, 2020)

for easy i would do two tanks.
one with the high pressure
the second with a pressure regulator set at the low pressure
then use a valve to switch between the tanks.
on the low pressure side use a valve with a sensor set at the exact low pressure with a relay on the dump valve.
set to close the valve at 15 psi. or just do a manual dump valve... but then you have the risk of loosing the bead on the tire.

you may have to go digital control like they use in the air ride bag systems to get the low pressure control you want with almost zero differential.
that is why i sent you over to the air bag system site.
most air compressors have 15 psi differential or more on the cut in and out sensors.
and same 15 psi differential on the analog pressure switches.

if this was a 4 tire setup
i would do the 4 corner bag control system. with the 4 corner digital display.
that way you could have more or less pressure on a tire set depending on where you are driving.
and you could dial in the exact pressure you need.

if it was a 6 tire system you could split to front and rear with a 4 corner system.


----------



## MacMcMacmac (9 mo ago)

You need a "negative" style pressure regulator.


----------

