Pump to recirculate during mashing

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Blinky

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Hi,

I currently have a 3 vessel brewing system - tea urn, jam boiler and picnic hamper. I am wondering whether I can improve my abysmal efficiency by recirculating the mash but have a couple of questions....
Would this do the job?
https://www.ebay.co.uk/itm/FOOD-SAF...703181?hash=item1a2b4e538d:g:3iYAAOSwjL5ZCzSA

My picnic hamper has a false bottom filter thing, would I draw off from here and dump back on top and if so would it not just end up pulling all the malt down and clogging it up? Or do I just simply stick the in and out pipes in the mash and let it recirculate in there?

Is this a bad idea? I dont have any way of heating the mash on its way round, would I end up loosing too much heat over the space of the 1 hr mash? If it is silly, would I still be able to use this to somehow spray water when sparging by connecting it to my tea urn?
 
Hi!
That pump will certainly do the job; I believe that you may be able to pick it up a little cheaper, but remember that there will be shipping costs to add on if you order from other places.
Angel Homebrew have a similar pump with better specs, but it doesn't have SS connections.
Brew Builder have an almost identical pump.
If you don't mind the long shipping time, this pump from China looks good at £50.
These pumps need to be primed - they will not provide "suction".
You will most certainly lose too much heat if you recirculate from your picnic coolbox. You would take the outflow from the tap and pump it back up to the top of the mash. You need some form of heating the mash and some form of control over the temperature to avoid overheating.
 
I think Bigcol has covered the pump questions, I suggest that unless you have reason to think this will improve your efficiency adding a pump to any setup that doesn't need it is more hassle than its worth. I suggest you look more into why your efficiency is poor 1st. Apologies and please ignore me if you already know for some reason this will fix an issue you have.
 
Are you lautering and sparging correctly? What's the temperature in the mash tun like after the first 5 minute and at the end?

I mash in a fermenter bucket (with a false bottom and valve) wrapped in several layers of camping mats. My temperature control is pretty woeful but I still get good efficiency, so a coolbox should be pretty good.

All the starch and enzymes start off in the grain, and the sugars dissolve into the wort as time goes by, so circulating the wort (or just stirring the mash) will speed things up as it brings the enzymes and starch out into the liquid, but in reality almost all the starch is converted very quickly (15 minutes or less), the full hour isn't doing much more. I bought one of the cheap solar pumps off ebay, not to improve efficiency just to reduce the mess of juggling valves, hoses and jugs of hot wort whilst lautering! I plan to just use it after the mash out for a few minutes to get the wort clear.

My tip for sparging efficiently is once you've added the boiling water to mash-out (and checked the temperature), then put a bit of tinfoil folded to make a pillow on top of the mash, that way as you laueter it doesn't disturb the grain. Once the wort is clear, carry on draining the wort until the grain is at the surface, then add the sparge water on top of the tinfoil again. This way the sparge water won't mix with the sugary wort and should give maximum extraction.
 
My setup is about the same as yours, 40 liter boiler and cold box (picnic type). I upgraded the box by making a wooden frame and adding 100mm insulation board to top, bottom and sides (this is relevant to how I mash).

My conversion was poor until I changed my mashing technique and I don't sparge at all!

My typical brew day mash example...
4kg Malt @2.5 L/kg

1st mash strike with 10L, mash in and leave for 1 hour
1st mash top-up 8.5L @ 1-2 degrees above mash temp, stir well and leave for another 15 minutes.
Drain off 1st mash...
2nd mash with 15L @ 1-2 degrees above mash temp., stir well and leave for 1 hour.
Drain off 2nd mash

In this example you should get about 22L in the fermenter after boiling for 1 hour.

Since changing to this method my conversion has been very good, but more importantly its been consistent.
 
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If you can pull the coolbox appart it might be worth it to check what insulation is in there, some cheap ones just have a brick of polystyrene between the inner and outer skins rather than moulded polystyrene (so lots of air around the edges where they don't meet). Might be worth packing it with something else if that's the case (glass wool?)
 
Just to throw a couple more options in, I'm also looking at buying a pump and had seen this one https://www.themaltmiller.co.uk/product/magnetically-coupled-pump/ and the same one from Keg Kingdom a bit cheaper: https://www.kegkingdom.co.uk/products/brew-pump-3000 (I've not ordered from either site before). They look like the same one from China that Bigcol linked, probably near the same price with shipping. Haven't found anything cheaper rated as good.

In regards to improving efficiency, this was my main reasoning behind doing this as well and was going to go down the immersion chiller in the HLT route then back through sparge arm to raise the mash temp. Is that not worth doing? My mash usually sits a degree or two out after 60 mins, but I like the sound of better wort clarity and extraction pre-boil. I find the whole HERMS system a little confusing but adding more complexity makes brewing more fun!
 
If you can pull the coolbox appart it might be worth it to check what insulation is in there, some cheap ones just have a brick of polystyrene between the inner and outer skins rather than moulded polystyrene (so lots of air around the edges where they don't meet). Might be worth packing it with something else if that's the case (glass wool?)

Ha Ha, mine is a cheap one, first thing I did was too drill a few small holes in the outer skin and fill the void with expanding foam.
 
Mine is a good quality hamper and holds the mash temp fine - I just like tinkering with things!
 
I was getting 50 - 70 % for my first few AG's in a very similar setup using a fly sparge technique. There was no consistency at all.

I gave batch sparging a go last brew and hit 80%. Same base malts as previous brews etc so the only thing different was the sparge technique. I've only had one go at it so can't yet vouch for consistency but would recommend trying batch sparging before splashing out on pumps and everything else required along with it.
 
One other thing to check is how accurately you're weighing your grain, and measuring the volume in the kettle.

After a few brews of being quite slapdash and wondering why my efficiencies were all over the place, I calibrated my kettle (filled it with a litre at a time and put a mark on the side) and weighed my grain (rather than trusting 500g bags to be exactly that). Lo and behold my efficiencies fell into line with what I expected.

One thing to bear in mind is that water in the kettle is about 4% less dense than water in the fermenter (or tap water), so 21l in the kettle is actually only 20, so if you measure it's gravity by refraction, then multiply that by the volume you get a much higher efficiency than you actually achieved. 4% doesn't sound like much, but it's about the same as the OG of the beer, so the actual density in the boil is ~1.00 g/cm3 @100c which increases to the OG as it cools. So when calculating efficiencies be very careful with which volume you use (pipette a sample of wort onto a tile to chil it rapidly, then onto the refractometer, then calculate the cold volume of wort in the kettle).

That and lautering/sparging is equal parts art and engineering. Actually It's all engineering, but without resorting to Coulson and Richardson Volumes 1 & 6 it's easier to say "just do it slowly and gently". If fly sparging doesn't give you the highest efficiency consistently then you've got channeling issues in the grain bed. Done carefully you should see a sharp drop off in the gravity as the water comes through which also allows you to avoid tannin extraction (only really an issue in weaker brews with high mash efficiencies).
 
A good strike temp which when well mixed in leaves you at your optimum mash temp followed by maintaining the temp as steadily as you can with insulation should provide you with the optimum conditions for your mash and provide the basis for a reasonable BHE.

batch sparging works for me btw..

adding a pump with or without any form of active heat input is adding complexity to the brewday when imho you should be able to achieve 75-85% BHE with the kit you have using well modified grains that have been malted and crushed within 12months of use.

if using older grains buying some freshly crushed malt and suplimenting the grain bill with a handful or 2 of the fresh stuff should fortify the ezymes for the mash,

when it comes to insulating the tun everything and anything can come in handy i used to pull all the coats off the coat rack and layer them round and over the tun..

check your thermometers are reading true?? if your reading off the wrong temps your mashes are probably disadvantaged from the outset. google 'eti thermapen manual pdf' https://thermapen.co.uk/ThermapenGuidebook-2015.pdf and when found it will contain detailed instructions for close to 0c and close to 99.9c calibration tests using ice and boiling water which can validate your thermometers.. (pages 16-20 iirc)
 

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