• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Repairing Azoo regulator

xim

Member
Joined
19 Mar 2010
Messages
499
(Of course, at your own risk)

Last month my 6 years old Azoo (adjustable pressure model) regulator got frozen up, literally.
It was covered with frost. The gas blew through the regulator safety valve.
Working pressure was beyond the max value on the gauge. It was strange that no gas was
delivered into the aquarium. I thought that was because the opening got clogged with the frost
as said in: http://www.harrisproductsgroup.com/en/Expert-Advice/Articles/CO2-Freeze-Up.aspx

So I disconnected it and replaced it with a yeast system, thinking this might be the time
to buy a new one. But before all, I wanted to find out what was broken.

From what I saw on Google. Each regulator might have different looking parts but most
were easy to take apart.

diagram%20Cornelius_zpsjtk7u8oj.jpg


And so was my Azoo...
repair-1_zpsltfhvbqn.jpg
repair-2_zps2hboswi6.jpg


The working pressure gauge was screwed up badly that the needle couldn't reach zero anymore.

Upon opening it up, I immediately noticed some rubber-like debris in the regulator body
(you don't see it in the photo because I have cleaned it out). Some of it still stuck out of
the little hole in a bolt where a poppet valve resided.
 
I had to use a deep offset wrench to remove the hex bolt that held the poppet valve.
Then it was clear that the debris was from the poppet valve sealing material which
I believed was made of polyurethane. It was worn out.

repair-3_zpstudiq1df.jpg


In case, you want to see the regulator body without its innards.
repair-4_zpscaynzdr0.jpg
 
Since the back side of the seal was still smooth, so... hehe. I trimmed the worn side with
a knife, making it as smooth as I could. Put the seal back, with the unused side facing out,
and thought I'd got a new poppet valve at zero cost.

repair-5_zpssubrrcvb.jpg


repair-6_zpsap65mkt5.jpg


I put everything back together, turned the regulator away from myself, in case it blew something out
with the full pressure. I couldn't cross my fingers because I must grip the CO2 bottle with
one hand and turn the bottle valve open with another...
 
It held the pressure! :woot: So I put it back to use and couldn't stop smiling.

But an hour later, the bubble stopped, the working pressure dropped to zero.
And I couldn't adjust it up, even when the adjustment bolt turned all the way...

After spending hours trying to figure out what's wrong. I had tried many things,
including one that triggered the regulator safety valve for another time and got
to know that the vale was self healing type, which was great that I didn't have to
replace it too.
 
At last, the answer came from a picture of Victor's regulator seal-seat which
looked very similar to my regulator's.

victor%20seal%20seat_zpsaqsishbn.jpg


Its sealing surface was flat but mine was bulging! Because I tightened it too much. I had figured
it would give better seal with the seal ridge of the bolt. Silly me!

As it turned out, what I did made the rod of the poppet valve stick out too short
to reach the plate of the diaphragm. So when the gas, that initially rushed into
the diaphragm's chamber before the poppet valve made a seal, ran out. The diaphragm
collapsed but the plate couldn't push the rod and got replenishment, thus the
dropping working pressure.

too%20short%20vs%20normal_zpsu2eciu0l.jpg


After the trials and errors, the original seal was not in a good shape anymore. So I cut a piece
of my polyurethane CO2 hose, spread it out, trimmed it to shape, drilled a hole, and used it as
a replacement seal, without over-tightening this time.

The regulator has been working fine for a month and a half now, knocking on wood :)
 
Last edited:
Polyurethane is not a good choice it is mechanically attacked by CO2, which could probably be why your regulator failed in the first place. Takes a while but CO2 is soluble in polyurethane. Search the paintballing sites for all the issues they have had with polyurethane seals in cheap Chinese paintball guns. PTFE is the way to go for sealing CO2, like the seal on the extinguisher.
 
  • Like
Reactions: xim
Hmmm but I read PTFE has cold creep problem unless it is the "filled" type.
May be that's why Victor's High Purity series use PCTFE as the material for
the seal seat while some other models use polyurethane.

Well, polyurethane might not be the most suitable material for CO2. But it is easy to find for me.
So I think I will keep changing it every year or two, which is very OK. Just hope my repair will hold up. :)

Regulators need to be overhauled every 1-5 years anyway, according to this guide:
http://www.scottecatalog.com/dsguid...dab60763c15a8267852568f2005ca6a0?OpenDocument
 
74A5A68B-11A1-40D2-8809-B99017F66004.jpeg
59B353AB-30D4-41BC-95AA-9A937EB59F36.jpeg
I guess I blew out the pressure saftey regulator. I do not find any part anywhere that would go here (on the floor, ceiling etc..). Do you know what can be done to reset the valve?? Thankyou!!!!
 
Back
Top