Klarstein Maischfest and Mashing

[matt76]

For those interested. I have attached the pump to some quick releases and then a switch into the bench (the red thing to the left). I'm able to control the flow by adjusting the valve on the tap.
For cleaning, the pump is on a slider that comes off nicely.
Its currently using silicone hosing but it's taken on some nice colours. If anyone can suggest something better I would appreciate it.
View attachment 41116

This is really interesting Since reading this thread I'm starting to think more seriously again about rigging up a pump.

Question - how is the wort returning to the kettle at the top? Do you happen to have any pics?

I was thinking about this - there's a breather hole in the lid but it's far too small for a 10mm-ish hose to poke through. So I'd have to enlarge this hole or drill a new one.

Other option is simply to crack the lid open a bit during the mash to poke the hose through but then you're losing heat which kinda defeats the object!

 

[Broken Toe]

This is really interesting Since reading this thread I'm starting to think more seriously again about rigging up a pump.

Question - how is the wort returning to the kettle at the top? Do you happen to have any pics?

I was thinking about this - there's a breather hole in the lid but it's far too small for a 10mm-ish hose to poke through. So I'd have to enlarge this hole or drill a new one.

Other option is simply to crack the lid open a bit during the mash to poke the hose through but then you're losing heat which kinda defeats the object!

The example isn't the best as I was trying to test the upper limits of the grain basket. I promise it isn't normally this messy..

I have attached a rachetting pulley system to the basket so i raise it slightly off the bottom to thicken the mash and encourage flow/ water movement. That way the thermostat controls the water at the bottom that I then pump over the mash. I figured I don't need to worry about covering it for this reason. But I will throw a bar towel over the top to stop any dust.

I want to make a little sparge arm for it to deliver the water back but i am lazy...

 

[matt76]

Ah, okay, I see - you're mashing indoors and lid off. I'd have to figure something out as I do my brewing outdoors in the garden. Drilling holes in the lid isn't ideal but certainly not out of the question (and to be honest I don't see too many alternatives).

 

[matt76]

I've been mulling this over for the last week or two and decided to bite the bullet and try rigging up a recirc pump on my Klarstein - I've sourced the various bits from eBay which have been arriving over the last few days so I decided to give it a test this afternoon.

No wort or mashing at this stage, just a few litres of cold tap water.

- I had some 9mm ID (12mm OD) plasitc pipe in stock which is a tight squeeze but fits snugly on the nozzle on the tap on the kettle
- Pump (search for mash pump on eBay, they're about 25 quid)
- 12V 2A power supply
- PWM controller to control pump speed
- Wire spring clips to hold the pipe in place

Well, the best laid plans and that..... In the test above I couldn't actually get the pump to run. Also, the pipe is a bit big for the connectors on the pump so that was leaking (note wet patch visible on the towel!).

I tried again later at the kitchen sink and at least got it running. I found some jubilee clips to clamp the pipe much more tightly which reduced the leak but it was still weeping - I think the pump connectors really want 7 or 8 mm ID pipe... I think the clips should be there just to make sure it doesn't come apart rather than needing to be there to stop it leaking...

For some reason the PWM controller won't play - not sure why as electrically everything was fine when I tested it with a meter. Pushcome to shove it's a nice to have and I could make do without. I think the issue might actually be that the power supply isn't quite man enough - it's 12V 2A, same rating as the pump but maybe it just needs a bit more oomph in reserve

So, back to the drawing board for now. I'm in no hurry so can take a bit of time to source extra bits as required

 

[Broken Toe]

I really like the idea of adding in the PWM. If you get it working I will be mighty interested in adding that to my setup also.

 

[Ashman]

I Tried PWM modules on alternative setup to limit pump speed and for me they didn’t work that well. They made the pump noisey and limited the maximum (100%) flow. When I removed them all was well so I think valves on output will be better option.

 

[Burtsbeets]

I am looking to get a 12 V pump for recirculation and am curious if anyone had bothered with a hop filter/bazooka as well?

I am mainly concerned with the pump blocking during the recirculation. But also know it is not possible to fit a bazooka and the grain basket!

 

[matt76]

I am looking to get a 12 V pump for recirculation and am curious if anyone had bothered with a hop filter/bazooka as well?

I am mainly concerned with the pump blocking during the recirculation. But also know it is not possible to fit a bazooka and the grain basket!

This is something I considered in my eBay browsing above.....

I thought about a fuel filter - this kind of thing though not necessarily this specific one. However, my concern is they're not specifically food safe and I worry they may have grease or oil in them.

So for now I've decided not to bother - my reasoning here is I actually use two grain bags in the mash. One is pretty coarse and holds the grain, the other is a very fine weave nylon bag - really a very large hop bag. The latter is effective at filtering grain husks, silt and sandy material and even hop sludge.

My hope is this will be sufficient filtering to protect the pump. And if I'm wrong then I guess I'll be buying a new pump + filter!

By the way, this is the pump I bought. Search for homebrew mash pump on eBay, there are literally dozens of suppliers. I think this one is quite cheap and cheerful - there seem to be some more expensive (=better?) ones, but for me this is a good enough starting point.

I went for a 2A power supply but I'm gonna try upgrading this to 3 or 5A as I suspect 2A is not quite man enough (categorically I am not an electrical/electronics expert!). Again search eBay for 12V power supply, or raid your cupboards at home!

 

[Burtsbeets]

Yeah, I would be a little unsure about using something like that. Depending on the mesh size of the filter, you may get a blockage. Also, it doesn't look to easy to clean from what I can see.

I do have a grain bag, that came with the klarstein, but elected not to use it in trying to get a reliable temperature. I guess this may be enough to stop the solid particulates. I am not too worried about the "soft" solid agglomerations that happen during the brew.

Cheers for giving us a view though.

As for the power supply, your pump is rated to 18W. So a 12 V supply working at 2A is able to supply 24 watts, if I have the right idea. So, unless you get a new pump, you should be fine for now. I am sure it will let you know when you are drawing too much haha.

The pump I am thinking of buying is this one here, its rated at 8.5 W so have bought a 12 V 1A plug (which I will also use with a homebuild magnetic stirrer!).

 

[Broken Toe]

The pump I am thinking of buying is this one here, its rated at 8.5 W so have bought a 12 V 1A plug (which I will also use with a homebuild magnetic stirrer!).

This is the one I have. It deals with the wort well, I don't use a bag. The only time it has blocked is when I get the the break material when pumping out. And a bit of tapping and shaking got it moving.

 

[matt76]

Yeah, I would be a little unsure about using something like that. Depending on the mesh size of the filter, you may get a blockage. Also, it doesn't look to easy to clean from what I can see.

I do have a grain bag, that came with the klarstein, but elected not to use it in trying to get a reliable temperature. I guess this may be enough to stop the solid particulates. I am not too worried about the "soft" solid agglomerations that happen during the brew.

Cheers for giving us a view though.

As for the power supply, your pump is rated to 18W. So a 12 V supply working at 2A is able to supply 24 watts, if I have the right idea. So, unless you get a new pump, you should be fine for now. I am sure it will let you know when you are drawing too much haha.

The pump I am thinking of buying is this one here, its rated at 8.5 W so have bought a 12 V 1A plug (which I will also use with a homebuild magnetic stirrer!).

Oh bobbins, how did I miss that one??!!

Hey @Broken Toe , any idea what size the brass outlet fittings are? I mean what size pipe (inner / outer dia.) fits? They look a bit bigger than on the pump I bought

 

[matt76]

Aha! I think I've cracked it now... I've had another little play this afternoon...

I think the PWM controller simply isn't going to work - not sure why but this means I need to wire the pump directly.

I added some PTFE tape round the pump inlet & outlet barbs which seems to have cured the leaks.

Getting the pump to actually run is a bit awkward - once it's up and running it seems perfectly fine, but it seems a bit fussy if it's not completely primed and there are still air bubbles inside the pump or in the inlet tube.

@Broken Toe How does your pump behave in this regard?

But once up and running it seems to deliver about 6L/min. That feels a bit high but we'll see. I tried using the tap on the kettle to throttle it back but it sounds like the pump quickly starts to struggle. I think a restrictor on the outlet would probably work better.

Anyway, it's progress at least. Next step is to try it with hot water and see if it still all holds together.

 

[Broken Toe]

I mean what size pipe (inner / outer dia.)

Off the top of my heat I think inner is 8mm and then held in by some very tight zip ties. I will nip out to the garage later when the boys are in bed and measure up.

@Broken Toe How does your pump behave in this regard?

I'll be honest. I've never had this problem. It could be down to bad practice and cutting corners. But I always leave my tap open and then cycle the pump on and off so there is always a back pressure acting on it.

But once up and running it seems to deliver about 6L/min

You are a meticulous man. I like your way of working.

 

[Broken Toe]

I will nip out to the garage later when the boys are in bed and measure up.

ID 8mm OD 10mm. It's a very snug fit.

 

[matt76]

ID 8mm OD 10mm. It's a very snug fit.

Cool, thanks for letting me know dude

After today's tinkering I think I'll hold off on ordering anything smaller - the 9mm ID tube seems ok so far if I use some PTFE to help it seal, I just need to test it with hot water next

 

[AdeDunn]

I've never owned a maischfest, but I did used to own a similar boiler, the ACE one. It had a bag not a basket, and a false bottom, but I had to work around similar problems, as did quite a few other brewers at the time.

For mashing, I built a simple recirculation system using a mini mag pump from brew builder. You control the flow using a tap on the output (not the input), so no need for PWM etc. Insulation I used an exercise mat and the bubble type insulation stuff.



A tip, don't go as far down as I did with your insulation.... I put a hole in the lid using a Q-Max cutter, on the underside of the lid I mounted a T fitting for the return.



The connections are all either quick disconnects or camlocks by the way, so the hose came away easily, as did the pump assembly etc.

If I wanted to brew a larger volume, I'd either heat some water up in a large pan on the stove top, or just do a cold fly sparge (still worked).

When it came to the boil, well I fitted a larger bazooka with the end bent over so it would fit in there. I then made sure to use either all whole (leaf) hops, or at the very least mostly whole hops. These would then form a filter over the bazooka, giving me lovely clear wort when it came time to transfer. If I had no choice but to use pellet hops, I'd bag them. At least some whole hops though would help to filter out the proteins from the wort when it came time to transfer.



Just to note, you are going to find buying anything Klarstein increasingly difficult for a while. Klarstein themselves aren't shipping to the UK right now (their couriers won't ship here...), so it's just going to be stock already over here held by 3rd parties.

Oh and I have one of their Brauheld Pros now.

Hope somebody amongst you maybe finds this useful. It made many good beers, before one of the cables in the bottom burned right through, and I built a DIY eBIAB rig that I used for a while.

 

[matt76]

@Broken Toe and @AdeDunn did you notice any changes as a result of installing your recirc system?

Specifically, did you notice any difference in efficiency? This is not a driver for me at all, just curious is all.

My objective is to get a more even and constant mash temperature, and hence (hopefully!) get a more consistent prediction of FG (or at the very least remove one big area of uncertainty!).

(I would add the beer is fine, but I'm an analytical kind of guy and it grates at me knowing the mash temperature is all over the shop!)

 

[Broken Toe]

I don't think the efficiency has changed by any considerable amount. But what it has given me is more consistency with the final attenuation. When I was eski mashing it would end up all over the shop. Now it is consistent and predictable (within reason). Without taking constant mash temps at different depths to test it. This is good enough for me.

 

[Gerryjo]

I have done a few brews now and just finding out how to use my Klarstein the first 2 were very cloudy and as u said temp varied . I manage to make a pump with odds and sods i had in my garage.
The last 2 with the pump have been clearer and it maintained a better temp with a jacket . I used a led dimmer switch to turn down the pump so it did not run dry at the bottom. All the brews have been very drinkable so i have been happy with it .

Try one of these as they're brushless and cheap,I've had them running my mashtun with no issues as long as you filter before the tap.

 

[AdeDunn]

I was able to hit over 75% efficiency without the pump, but yeah definitely more consistency thanks to more even mash temps. More importantly, no need to vorlauf (I love nice clear wort into the boil) as the pump did it for me in effect.

I used the same pump when it came time to cool, pumping through a special jet setup I made, into the immersion chiller I used to use.

I went with this pump, the only time it clogged was the time that paper towel got into it (long story). I still have it in fact, and it continued to serve me on my eBIAB rig, and may even get pressed into service again one day, who knows? lol