Tips on getting a decent flow through my CFC without a pump?

[Croy9000]

I went through great lengths to build a brew stand to take advantage of gravity in draining wort from the BK through a CFC.

But I am having a hell of a time getting a decent flow of water through the CFC in my tests. I havent even brewed a batch yet, just been testing with water. At best I am getting a trickle, and thats without hot break, hops, etc.

My BK valve, and tubing is all 1/2" (but the CFC is 3/8"). I just cant figure out how to get the air out of the line. I tried pre-priming the tubing with forced water via a hose, but air manages to get right back in when I switch the tubing back to my BK.

Short of a March pump, any tips? I hate to get a pump just for that last stage of the process.

 

[Ohio-Ed]

Not sure a pump will help you a lot. Any chance you kinked the copper? Mine doesn't flow real fast, but I think the small diameter would restrict a pump also. How long does it take to run 5ga through?

 

[wilserbrewer]

More head would help the flow...as in a greater height differential...haha.

 

[ShortSnoutBrewing]

Not sure a pump will help you a lot.

Don't have an answer for the OP, but this statement is just silly. A pump would be a HUGE help. I had the same issue and finally tossed in the towel and purchased a pump. Best purchase I've ever made.

 

[Croy9000]

I just timed 5 gallons. It took 21 minutes, and again, that is debris free water.

Here is a pic of the water flow immediately after my BK ball valve. Pretty sad.

Forgot to mention I have a dip tube of sorts.

Man, I feel like I am at a urology examination.

 

[shortyjacobs]

Wait, that's out of your BK? You have air in the system right out of the BK. That to me says you have air getting in right at the BK, not in the CFC. What happens if you just drain the BK without hooking up to the CFC? (attach a 3 ft section of hose, let it hang down, open the ball valve)....if you have air in the line then, you have to tighten everything up some...

 

[Sawdustguy]

Wait, that's out of your BK? You have air in the system right out of the BK. That to me says you have air getting in right at the BK, not in the CFC. What happens if you just drain the BK without hooking up to the CFC? (attach a 3 ft section of hose, let it hang down, open the ball valve)....if you have air in the line then, you have to tighten everything up some...

+1 I think Shorty hit the bail on the head.

 

[Croy9000]

If I unplug the end of the 3' hose attached to the CFC and just let it hang the BK drains in minutes, nice full blast flow. It drains perfectly right down to the mouth of my dip tube like it should.

"I assume" the issue is that the CFC is full of air, and most of that air rises up to the top of the hose by the ball valve. The water is never able to build any static pressure.

 

[weirdboy]

Just get a pump. It doesn't have to be a March 809 series. You can get a little submersible aquarium pump to pump ice water through your CFC. They cost maybe $20.

 

[shortyjacobs]

If I unplug the end of the 3' hose attached to the CFC and just let it hang the BK drains in minutes, nice full blast flow. It drains perfectly right down to the mouth of my dip tube like it should.

"I assume" the issue is that the CFC is full of air, and most of that air rises up to the top of the hose by the ball valve. The water is never able to build any static pressure.

Hmmm....I don't buy it. If you have full blast flow, then that full blast flow should blast the air out of the CFC. Think about it. When you start a siphon, does air fight its way back UP the siphon? No....it flows down and out.

With many inches of head on top of that BK ball valve, plus another foot down into the CFC, I just can't see air in the line being an issue.

What happens if you pinch the line between the BK and CFC, then let go again? Pinching should build up a "slug" of water, which should then siphon down and out nicely....

But I'm still betting on sucking in air somewhere....

 

[shortyjacobs]

Just get a pump. It doesn't have to be a March 809 series. You can get a little submersible aquarium pump to pump ice water through your CFC. They cost maybe $20.

I think his issue is that the wort doesn't flow fast enough, not the cooling water....he'll need a March 809 to move the wort, (if he goes that direction).

 

[samc]

What if you put a http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=66418 at the end of your CFC to get a good suction started? When the flow starts pull it off.

 

[Sawdustguy]

Just get a pump. It doesn't have to be a March 809 series. You can get a little submersible aquarium pump to pump ice water through your CFC. They cost maybe $20.

Re-read the original post. His problem is not with the cooling water portion of the CFC, it on the wort portion. The aquarium pump would be of no help to him.

 

[Croy9000]

Hmmm....I don't buy it. If you have full blast flow, then that full blast flow should blast the air out of the CFC. Think about it. When you start a siphon, does air fight its way back UP the siphon? No....it flows down and out.

Yea, the air will be forced out if you get a full blast flow, something is restricting it though. Just to note: there is a bunch of air sitting at the top of the hose, and a backlog of water sitting at the bottom of that hose at the head of the CFC. The hose coming out of the CFC to my bucket looks much the same as my the picture at the top, just a slow tricking flow.

I am starting to wonder if 25' of 3/8" copper in the CFC is just to much resistance for gravity to initiate an air purging flood of water. That or as someone mentioned previously, I have a kink (although this is a brand new, store bought CFC for what its worth).

What happens if you pinch the line between the BK and CFC, then let go again? Pinching should build up a "slug" of water, which should then siphon down and out nicely

Pretty sure I tried that. The issue was pinching it just stops the flow from the BK due to the compression of air above the pinch.

 

[Croy9000]

What if you put a http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=66418 at the end of your CFC to get a good suction started? When the flow starts pull it off.

Interesting. I may look into that. Thanks for the link.

 

[JVD_X]

You can try adding a sight-tube with a thermometer port but instead of using the thermometer put a valve instead. Then drain through that port. This might allow the air to go up and escape through the site-tube.

At worst... you have a sight-tube.

 

[Bobby_M]

Pinch the hose between the BK and CFC, just before it hits the CFC. Don't stop the flow, but reduce the flow so that water builds up ahead of the pinch, then let go. The other thing you can do is attach a hose to the end of the CFC draping down into your fermenter, but I'm sure you have that. Hold the end of that up a bit so that water collects in the bottom of the "U" shape, then drop it down.

 

[Croy9000]

Success! The solution was vibrating the hoses. I started with the BK to CFC hose and kept vibrating it to break up the air into bubbles. I made sure there was a small upward arch in the hose right at the CFC head so the bubbles would collect there and get swept into the CFC. Only took about 10secs of vibrating. After all the air was gone from there I did the same at the output end.

Result? A 5 gal drain in 9 min. A significant increase over the 21 min from before. Phew!

The tip about holding up the output end of the hose to prime before starting the drain helped a lot to, thanks Bobby. Thanks for all the other great input from everyone.

I really think the issue is as I mentioned before, the restriction of the CFC wont allow the flow to overcome the significant air pockets in the system. In hindsight I should have researched the existence of 1/2" CFCs.

 

[weirdboy]

Re-read the original post. His problem is not with the cooling water portion of the CFC, it on the wort portion. The aquarium pump would be of no help to him.

Ah, right you are. My mistake.

 

[Croy9000]

Also, I thought it notable that I was able to positively determine I had a sealed system with no leaks. After getting a good flow of water I turned off the ball valve. The flow at the other end of the CFC instantly stopped, and hardly a drop dripped from the output in the minute I left it like that. A leak would have allowed water to drain out.

 

[Bobby_M]

Keep in mind that draining faster than 9 minutes wouldn't be a real advantage until your tap water temp was down below 60F anyway.

 

[shortyjacobs]

Success! The solution was vibrating the hoses. I started with the BK to CFC hose and kept vibrating it to break up the air into bubbles. I made sure there was a small upward arch in the hose right at the CFC head so the bubbles would collect there and get swept into the CFC. Only took about 10secs of vibrating. After all the air was gone from there I did the same at the output end.

Result? A 5 gal drain in 9 min. A significant increase over the 21 min from before. Phew!

The tip about holding up the output end of the hose to prime before starting the drain helped a lot to, thanks Bobby. Thanks for all the other great input from everyone.

I really think the issue is as I mentioned before, the restriction of the CFC wont allow the flow to overcome the significant air pockets in the system. In hindsight I should have researched the existence of 1/2" CFCs.

I sit corrected. Glad you worked it out!!!

 

[Ohio-Ed]

Don't have an answer for the OP, but this statement is just silly. A pump would be a HUGE help. I had the same issue and finally tossed in the towel and purchased a pump. Best purchase I've ever made.

Keep in mind that draining faster than 9 minutes wouldn't be a real advantage until your tap water temp was down below 60F anyway.

That was my point in an earlier post about a pump not helping much... Looking at his stand, it appears he has plenty of height to gravity flow through his CFC. He didn't say how slow his flow was. It's not gonna do much good to pump 6 gallons a minute through a 3/8" cfc with tap water.
I have 2 pumps, but gravity feed when using a cfc so there is time to cool.

OP: Glad you got it figured out... 9 minutes is pretty good, you may have to partially close your ball valve to actually get the wort cooled. Also, you can stuff a SS pot scrubber under your pickup tube to kinda act like a filter to keep some of the break and trub from getting to your cfc.

 

[Bobby_M]

In my experience, the only thing that is likely to clog the cfc is whole hops so I'd recommend bagging those. Otherwise, that's the advantage of CFC over plate chillers; they don't get clogged with small particulate.

 

[Synovia]

In my experience, the only thing that is likely to clog the cfc is whole hops so I'd recommend bagging those. Otherwise, that's the advantage of CFC over plate chillers; they don't get clogged with small particulate.

Be careful with Plug hops too.

 

[Ohio-Ed]

I had mine clog once when I had a thermometer probe stuck in the CFC outlet. I guess there was enough back pressure that the small stuff started building up. When I finally cleared it with compressed air, it blew crap all over the shop.

Ed