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Try leaving the needle valve alone and turning your CO2 cylinder main tap open one more round.
Hi All
Just setup a new JBJ solenoid, JBJ bubble counter with a external reactor from NA. After adjusting the needle valve to the desired bubble count (about 45 bpm), it was working fine
Problem comes after the solenoid turns off, 12 hrs later, when it turns on again. Could tell from the light that the solenoid is turned on, but i do not see any bubble in the bubble counter. To get the set going, I have to turn up the needle valve to increase the bubble count and then turn it back to the original setting
There is a short tube between the check valve and the reactor. Seems like everytime the solenoid turns off, that tube gets filled with water as the co2 pressure has been switch off (this should be normal). When the solenoid comes back on, there don't seems to be enough pressure to push out the water, as such, no bubble appear in the bubble counter
Turning up the bubble count (pressure) pushes the water out of that tube and once that happens, the set seems to work normally
Anyone any idea where is the potential problem?
1. After the solenoid turns off, i turned off the tank. Waited for 24hrs and checked that there is no change to the reading of the pressure gauge
<I guess that means there is no leak from the tank connector to solenoid>
2. In case the check valve is the problem, will be changing to a spare one i have tomorrow to eliminate another item
3. I am using the integrated JBJ bubble counter ... not sure how i can test this. maybe will try the soap water test tomorrow
4. I guess these are pressured tanks, so i dont think the position of the check value matters right ?
Any help much appreciated
Try leaving the needle valve alone and turning your CO2 cylinder main tap open one more round.
Like you mentioned, there is pressure from the back-flush of the reactor.
Maybe you can observe the bubble counter after about 15 mins after the solenoid comes on? (Maybe longer if you are running the reactor on higher output filter, as pressure from back-flush would be greater)
By then, there should be enough pressure to counter the back-flush and you can start to observe your bubble counter.
Your setup sounds alright and should not be a cause of much concern.
Last edited by evolim83; 16th Jul 2006 at 04:41.
I think you have, what we call a "sticky" problem. The check valve might be a bit rusty inside...Originally Posted by evolim83
Hi Stephen
You mean the needle valve within the solenoid right? Let me check tonight, if i disconnect the tube leading to the check valve , there should be no reverse pressure from the reactor, if it is really a "sticky" problem, then it should not bubble too
evolim83
Left the solenoid on for more than 2 hours and still no bubble. Will try experiment a higher flow rate to see if it is a pressure problem or a solenoid needle problem
Thanks folks for the suggestions
needle valve is a separate device and definately not within the solenoid valve. however, the needle valve may be attached to the solenoid valve.
did you turn the co2 cylinder main valve sufficiently? about 1/2 ~ 3/4 should be good enough.
what are the pressure gauges reading before and after the solenoid is switched off?
are there any co2 bubbles if you disconnect the co2 line to the external reactor?
thomas liew
Yeah...I think it confuse with those that I used to work with at work. Sometime the solenoid is working but the valve is stuck. The most common cause for this to happened is, water got into the valve. And how water got into it and most of the time is the vapour in the air.
I am not familiar how the CO2 in those cylinder and being manufactured and pump into the cylinder. If the CO2 has a high concentration of water vapour very soon the valve will have problems.
Just my 2 cents ...
I am still having this similar issue, no matter solenoid or not. Happen on different regulator also. So really don't know what causing this ! Especially if you have a splitter.
Right now I am trying to run the CO2 24x7, even then, the CO2 count fluctuate.
maybe you'll like to elaborate on this.
are you having multiple needle valves or a single needle valve?
what are you using to diffuse co2?
you'll need to provide more information.
thomas liew
i doubt water vapour concentration will be significant. when cylinder is filled, there are liquid co2 in the cylinder. as co2 is heavy, i believe any water vapour that exist in the cylinder will be "forced" out first.Yeah...I think it confuse with those that I used to work with at work. Sometime the solenoid is working but the valve is stuck. The most common cause for this to happened is, water got into the valve. And how water got into it and most of the time is the vapour in the air.
I am not familiar how the CO2 in those cylinder and being manufactured and pump into the cylinder. If the CO2 has a high concentration of water vapour very soon the valve will have problems.
Just my 2 cents ...
for pneumatics, air is drawn from the surroundings. thus, there will always be water vapour in the compressed air. i believe this is why pneumatic systems always have dryer, auto purge, ... to remove the water vapour.
thomas liew
When solenoid is switched on, you would be able to hear a loud "tack". If there is no "tack" sound, that means either no current passed through or solenoid plunger is stucked.
Also, make sure the one-way valve is placed nearer to the reactor and in the right direction. So water don't flow back too far.
3way splitter with 3 needle valves.
I am using them for 1 external PVC DIY reactor (no longer use), 2 internal powerhead to rain bars. Initially I fitted with 3 brass type bubble counter (with check valve) on the splitter, the bubble count varies among all 3 of them daily. After that , I remove one, and use a plastic bubble counter (1 in and 1 out on top), with same bubble vary problem.
So now I run my CO2 24x7, check/adjust in the morning before going to work and after work.
Also note that I faced the same problem on the manual regulator (with 2 flow meter and flow nob) as well as solenoid regulator (like NA type).
Will high precision needle valve like swagelok worth investing ?
i don't think that there is a need to use high precision needle valves. unless you are trying to achieve something like <10 bubbles every minute. do you really need this kind of precision?
what is the output pressure of your setup?
believe you are still adjusting the co2 bubble rate. stop adjusting for a couple of days and see it the bubble rate will settle down.
thomas liew
Hi All
Thanks for all the advise
Soaked my check valve, no bubbles ..i.e. no leaks. Bubble counter is "integrated" so cannot soak it.
Tried turning up the pressure on my needle valve and it seems to work ok.
With the NA external reactor and a ehiem 2026, seem like anything less that 100 bpm will not build enough pressure to "kick start" the pressure.
Trying to experiment with "lowering" the pressure of my filter (as the ehiem 2026 is able to control the flow rate) ... lets see if that makes a difference
By the way, anyone knows what the other guage of a JBJ solenoid reads ?
One reads 1200 psi , which i know is the remaining pressure in the tank.
The other reads 2.4 kg/cm ... what does that show ?
Sometimes the gauge is stable, sometimes it swings between 2.4 to 2.8 ??
When the set is working ... it seems to be stable
by the way 100 bpm should be ok for a 2.5ft x 1.5ft x 1.5ft tank right ?
The octo and yamato looks ok ....
The other guage that show 2.4 kg/cm I believe should be the low pressure reading.
100bpm is only 1.66 bps... Might be abit low...
You can afford 3-4bps imo...
the other gauge shows the output/working pressure. this is the pressure of co2 gas between the output of your regulator and reactor.
the reading should be generally stable. pressure could be higher when solenoid is off.
thomas liew
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