Second Stage Creep Problem

[ffmedic7]

Greetings,

I am new to the CO2 world and just built a quality rig. I have a Victor HPT 500, Burkurt solenoid, the new Fabco NPT valve, and a GLA bubble counter and in-tank diffuser.

Here is the problem: I have noticed something strange yesterday morning before the timer powered up the solenoid; the second stage pressure was pegged! It was set to 30 psi during the day. It will slowly lower to set point when the power is on and gas is flowing, but I am noticing it creep up again when I turned the power off. This morning, the gas isn't flowing at all. The solenoid is warm, but didn't have that solid "click" sound when powered. Is it possible that too high back pressure will keep it from opening? Why would my second stage creep up?

Any thoughts?

Thanks all....

 

[Matt F.]

Greetings,

I am new to the CO2 world and just built a quality rig. I have a Victor HPT 500, Burkurt solenoid, the new Fabco NPT valve, and a GLA bubble counter and in-tank diffuser.

Here is the problem: I have noticed something strange yesterday morning before the timer powered up the solenoid; the second stage pressure was pegged! It was set to 30 psi during the day. It will slowly lower to set point when the power is on and gas is flowing, but I am noticing it creep up again when I turned the power off. This morning, the gas isn't flowing at all. The solenoid is warm, but didn't have that solid "click" sound when powered. Is it possible that too high back pressure will keep it from opening? Why would my second stage creep up?

Any thoughts?

Thanks all....

A bit of "creep" is normal when the regulator changes from having a constant gas flow to static pressure (solenoid closes). There should be an initial increase of 3-5 psi, but that is where it should stay (once it is shut off, after about 15 minutes, the low pressure gauge needle should stay put). What do you mean when you say the second stage was pegged?

With the A and B models you'll see this increase of pressure (to static) much more than with a C or D gauged regulator.

Burkerts are fine to over 100psi, but shouldn't be run much beyond that. I forgot which pressure is max (120psi or 125-ish). There is no reason you should run the working pressure more than 50 psi, imo, even with the new archaea-type diffusers.

If you Burkert is clogged, not installed correctly, or not opening/closing properly, that could cause a problem, but the low pressure gauge should not move 15 minutes after the solneoid closes. The pressure should not slowly increase over the night.

I think I remember the unit I sold you (see below):

 

[Matt F.]

iirc, I think it was this regulator:
the pics:

Originally from this thread?
http://www.barrreport.com/showthread.php/8308-Used-Untested-Victor-HPT-500

 

[Matt F.]

PM sent with some specific diagnostic questions.

 

[ffmedic7]

That's the one Matt. The low pressure side is pegged to 200psi by morning and it seems that the solenoid won't open with that much back pressure.

 

[Matt F.]

That's the one Matt. The low pressure side is pegged to 200psi by morning and it seems that the solenoid won't open with that much back pressure.

The regulator was connected to your system (which is pressure tested and no leaks). You set the working pressure to 30 psi. By morning it was 200 psi and the solenoid wouldn't open.

Have you tested for leaks in your post body?

How long has the system been running? Has it been running w/o issue till this point?

 

[crowfoot]

This is my speculation on what happened.

If the outlet pressure of the regulator increased from 30 psi to 200psi with the solenoid closed (no flow), then that is excessive pressure creep. This means that there is a leak across the seat, which is typically caused by contamination or foreign particles being lodged inside. (The seat is the seal between the high pressure and low pressure areas of the regulator.) When this occurs, the regulator loses it's ability to reduce the incoming pressure.

It is possible that the pressure went above 200 psi, because the gauge was "pegged" as you mentioned. If so, then the gauge may be busted. Also, the Burkert solenoid is rated up to 21 bar or 305 psi, so if the pressure went above 305 psi, then the solenoid may have been damaged. If I understand correctly, most electronic valves are designed to fail in the closed position, so that may be why it is not opening.

 

[Matt F.]

This is my speculation on what happened.

If the outlet pressure of the regulator increased from 30 psi to 200psi with the solenoid closed (no flow), then that is excessive pressure creep. This means that there is a leak across the seat, which is typically caused by contamination or foreign particles being lodged inside. (The seat is the seal between the high pressure and low pressure areas of the regulator.) When this occurs, the regulator loses it's ability to reduce the incoming pressure.

It is possible that the pressure went above 200 psi, because the gauge was "pegged" as you mentioned. If so, then the gauge may be busted. Also, the Burkert solenoid is rated up to 21 bar or 305 psi, so if the pressure went above 305 psi, then the solenoid may have been damaged. If I understand correctly, most electronic valves are designed to fail in the closed position, so that may be why it is not opening.

The Burkert solenoid, 00456786, has a working pressure range of 0-170 PSI. The Burkert Type 6011 can be rated to 304 psi.
I wouldn't run the mini 00456786 more than 120 psi. The solenoid isn't damaged (neither is the low pressure gauge). I spoke with the owner.

Here are the specs on the type 6011 solenoid:
http://www.iprocessmart.com/images/Burkert/DS6011-Standard-US-EN.pdf

Could be any number of things why the pressure is increasing when the solenoid is shut. Hard to say for sure without seing the unit in person. The regulator held 120psi of pressure, as seen in the link, while I was testing for leaks, etc. The difference between static and flow pressure should not be that drastic (7 or 8 psi is commonly seen).

When the solenoid is open, he says that the working pressure stays constant at 30psi, where it is set. Strange I say.

This unit was tested at 120 psi. There was no "creep" when I tested it for 1 hour on a co2 bottle.

Anyway, this is the first time I've seen/heard of a potential dud. I take that back, another member had an HPT270 fail. But it was not one of my own units.

I still have two questions:
1)are there any leaks anywhere from the postbody to the fishtank?
2) is the solenoid installed correctly

Either way, I have given this member a total refund of his money and sent one of my personal regulators, that I recently aquired from ebay, free of charge. So, I refunded the $120 plus gave him an HPT500 for free. I did this despite the fact that my posted warranty period is over. Refunds at this point are at my discretion. Of course I don't want to pass on a potentially faulty piece of equipment. In this case, I take the loss.