Looking for peristaltic pumps

My first brewing went quite well, I just had many congestions while boiling. I’m not sure whether the Tupsflo pump is actually to blame, but I reckon that with a self-priming pump I wouldn’t have run into that problem. While searching the Internet for pumps which are self-priming and designed to handle temperatures of 100°C, I came across peristaltic pumps.

There are a couple of videos with home-made peristaltic pumps which prove that they are acting quite well for mashing. Interestingly, there doesn’t seem to be any commercially available pumps designed for (home)brewing, even their mechanics looks rather simple. Has anyone an explanation for that or is it just a gap in the market?

If there are no good reasons against using peristaltic pumps, I’d definitely be willing to spend 200 - 300 USD for such a pump, especially if individual parts can be renewed if they become broken. So if someone wants to start a kickstarter project, I’ll be backing for sure :slight_smile:

-Marc

You’ve assumed a peristaltic pump would solve your issues, without actually saying what your issue is. What the problem could be with your boil that’s related to your pump is somewhat beyond me. There’s a lot of folks using normal pump without issue so that suggests your process or application rather than the type of pump.

The ability of a peristaltic pump to withstand high temps is related to the tubing selected. It took a single Google search to find tubing capable of a range from -47°F to 390°F. The speed at which I was able to find this suggests it would be relatively easy to find tubing to suit your application. It does not however suggest at all that it will solve your problems since you don’t say what they are.

I wrote this posting mainly to express my interest in peristaltic pumps and to hear what others think about it. My problem wasn’t to find suitable tubing, but to find a pump with reasonable flow rates for commonly used tubing in a homebrewing setup (in my case 35L kettles with tubing having 12mm inner diameter and 4mm walls).

Regarding my actual problem with congestions, I’ve posted more details here. If you have any ideas I’d appreciate to hear them. Nevertheless, I’ll remain interested in peristaltic pumps.

Okay, I’ll share what I think.

I think a peristaltic pump is a solution in search of a problem. I don’t see where it solves any issue that you’ve described. Where they really shine (accurate flow rates, low risk of contamination, sensitive or abrasive fluids, prevent backflow) are of little to no advantage for your application - in my opinion of course.

Because of their strengths, you will find them in areas which are well controlled, regulated and controlled. As such the prices are going to reflect their precision. Because the basic function is simple, making one that simply pumps is rather trivial and probably your best bet if you really want to do this. I saw a DIY “linear” pump made with a track that looked somewhat like a small snowmobile track if you can picture that.

Regarding tubing - that really is a concern whether you think it is or not, at least as you described your wants. You mentioned self-priming so the tubing would have to withstand negative pressure. None of the tubing I have seen in normal use in brewing would withstand negative pressure. I don’t think self-priming is something that helps you however because of the application. Self-priming creates a vacuum; creating a vacuum will force the trub and hops into the interstices where they will become lodged for the session, further complicating your issue.

Trying to follow the question posed and only discuss the relative merits of a peristaltic pump. I’ll reply to the other thread as well.

ETA: I guess I won’t reply to the other thread since it seems to be gone. I’ll just make my comment/question here:

Why would you pump/circulate while boiling? Or are you just doing it towards the end to sterilize the lines before pumping out? I’d think you might have better luck with the coarsest possible filter size to allow the hops to form a sort of filter around the tubing. Do you have enough tubing to make a double loop?

Thanks for your ideas, LBussy.

I didn’t understand that: what would be the problem of the negative pressure. I was just thinking that the tubing would be stressed heavily in the area where it was compacted. However, it could be replaced easily after some (tens of) hours of usage, if necessary.

That is a good question. I thought it was recommended, concluding this also from the fact that recommendations are to install the temperature sensor at the outlet (not directly in the kettle). If circulation during the boil isn’t necessary, it will at least be necessary during chilling where I had congestions as well. Here are the details from my previous posting:

Also, I’m using hop pellets in case this matters regarding the filter size – my impression was that the Lauterhexe was covered by a thin layer of slag, so (significantly) fewer liquid than the pump’s flow rate would enter the tubing, thus causing problems (which would be no issue if the pump was self-priming).

-Marc

The tubing I have seen used in brewing would simply collapse. I get the impression you may not be in the US so maybe the tubing you use is more rigid.

If you are controlling the boil and the sensor is in the outlet, yes, I agree you need to flow something. Maybe flowing at a much lower rate would help? I see circulation as a good way to cool the wort/lose heat so I think I would prefer to have the sensor in the kettle itself, but keep in mind this is coming from someone who does not have any of the newer automation so maybe I’m just old-fashioned.

I think smaller holes would clog up more easily even with a self-priming pump. Maybe the solution is as simple as a tighter bend?

That’s right. I’m using the tubing from the BrewPi store. It’s looks quite rigid, but I may be underestimating the power of a vacuum.

I could try this. But I guess in this case, I have to use something else as a fine filter for lautering. What are you using for lautering?

It looks substantial, I’m just not sure whether it would stand up or not.

I use a copper tube with slits in it (upside-down) for lautering. I don’t think of that as a filter so much as allowing the grain to form a filter. I don’t filter out of the kettle at all, I whirlpool and let it settle.

Peristaltic pumps are mostly used for very low volume precisely dosed flows, like administering medicine. I would not use them for brewing.

I have a valve below after my pump that I can shortly open if there is air in the pump. As soon as water comes out of the valve, I close it and the pump can pump back up to the kettle again.

I used to think that I got air in the tubes as well, but it is actually a vacuum because the pump create a big pressure difference. If you get this, the problem is clogging of the lauterhexe or grain bed.

For the mash tun, I make small bends in the lauterhexe when I drop in my grain. The weight of the grain keeps them in place. I don’t stir much, at least not the bottom layer.

You should also give the mash 10 minutes of rest after mash in. Do not start pumping right away. That will allow the grain bed to settle and form a good filter. When you start pumping right away, you can suck all the small particles to the filter.
Get your strike water to the right temperature to hit your first mash temperature and compensate for temperature losses in your setup. For example, strike with water at 75 degrees to hit 67 degrees.

In the boil kettle creating a good whirlpool helps. See my reply in your other thread about pinching the whirlpool outlet flat to create a better whirlpool.