Brew Pumps: Why a bleed valve?

Ok, so forgive my naivete, but I'm not certain I understand the point of adding a separate bleed valve to a pump setup.

I've seen configurations where the pump outlet is split, via a tee. One branch goes to the hose, the other goes to a side dump port. Both are controlled by ball valves.

It seems to me, the same could be accomplished just using a single outlet controlled by a ball valve. I picture bleeding going like this: I connect the pump inlet to the source, and open the valves (outlet hose end remains in my hand, not connected yet). The fluid from the source *should* flood down, fill the pump head, and start travelling back up the outlet hose which is in my hand, simply due to gravity.

Am I missing something here?

Sometimes the pump has a bit of water in it, and then you connect the line to the pump intake and connect the other end of the line to the vessel and then you open the pump outlet valve and then the vessel valve but the weight of the water inside the pump is greater than the air pressure in the line...so nothing happens. You're sitting there like a dummy with a hose full of air.

So what I do is open up the camlock on the vessel side a bit and that lets the air escape. Then, once the air is purged and it starts leaking hot water, I yell, "****! ****! That's hot!" and then I close up the camlock again.

Probably not the optimal process, but it works for me.

LandoLincoln said:

Sometimes the pump has a bit of water in it, and then you connect the line to the pump intake and connect the other end of the line to the vessel and then you open the pump outlet valve and then the vessel valve but the weight of the water inside the pump is greater than the air pressure in the line...so nothing happens. You're sitting there like a dummy with a hose full of air.

Click to expand...

I'm just not sure how this would be any different with a side bleed valve. Unless there is water in the outlet hose, which there shouldn't be, both provide an exit path for the outlet.

Your Idea will work but remember the liquid you are pumping is really hot. I did that for my first 2 tries using a pump. Then being distracted I got some hot wort on my arm, dropped the hose, yelled, doused my arm with cold sanitizer that was close at hand then closed the kettle valve. By that time I lost about a quart of wort and had a great big mess. Safety first.

OkashiiBrew said:

Your Idea will work but remember the liquid you are pumping is really hot. I did that for my first 2 tries using a pump. Then being distracted I got some hot wort on my arm, dropped the hose, yelled, doused my arm with cold sanitizer that was close at hand then closed the kettle valve. By that time I lost about a quart of wort and had a great big mess. Safety first.

Click to expand...

I see your point, but keep in mind this is all done with the pump off. The pump wont be turned on until the outlet hose is connected up, post-bleeding.

I don't see any risk involved, unless I'm missing something

Ashella said:

I'm just not sure how this would be any different with a side bleed valve. Unless there is water in the outlet hose, which there shouldn't be, both provide an exit path for the outlet.

Click to expand...

Yeah, I know. I'm agreeing with you. The only reason I can see for a side bleed valve on the outlet side of the pump is so that the brewer can connect all of the tubing and then open up the side bleed valve and purge the air (and catch the wort/water with something or just let it hit the ground) then close that valve and then turn on the pump.

Or...let's say you've already transferred the sweet wort into the BK and now you're sparging. So you do your vorlauf and now you want to transfer the sparged sweet wort to the already partially full BK via the BK's bottom dip tube/valve. And there's a bit of wort already sitting in the pump.

So now you have two lines to purge of air. You connect the hose from the MLT to the pump inlet and you connect another hose from the BK valve to the pump outlet. You open up the bleed valve and then you open up the pump outlet valve and then you (slowly) open up the MLT valve. So the MLT-to-pump hose fills with wort and you purge the air all the way from the MLT to the top of the pump. Close the pump outlet valve. Then you open up the BK valve and let wort flow from the BK to the pump bleed valve, purging that hose of air. Then you close the bleed valve and hopefully you're sitting there with two hoses and a pump full of wort. Open up the pump outlet valve and hit the pump switch and you should be golden.

That's the theory. The reality is that often the hoses still have air trapped in them and the easiest way to get rid of the air is by venting it from the vessel connection point. So it would make more sense to have a bleed valve installed on each vessel outlet instead of the pump outlet.

I agree that a separate bleed valve on the outlet would have limited value for the reason you describe. However, the setups I have seen with the T and bleed valve typically have it on the INLET side of the pump. For example, see

http://morebeer.com/products/march-pump-assembly.html

In this case, it addresses the water-in-pump issue that LandoLincoln raises. I say this all in theory of course, as I haven't had the chance to use my new pump yet. . .

A bleeder valve is not necessary, but a huge advantage as it is way easier, especially because you know exactly where the water is going to come out.
One option that I have not seen others use is a valve with a built in bleeder valve. The bleeder valve is a tiny thumb screw on the side of the valve just bellow the handle, but it is plenty to let the air out of the lines. I think they were only about $1 more when I setup my pump.