Crown Urn thermostat prevents reaching mash temp

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PuffinPunch

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Hey all
I'm just sitting down to try my first all-grain brew today with a new 40L Crown Urn (with factory mod, concealed element with strainer). Having an issue and wondering whether I'm doing something wrong.

I can't get the temperature to rise above 62c. Even with the temp dial set to max, the internal thermostat keeps turning off the heating element as if its at its target. Tried a few other temperatures in excess of my target but this hasn't helped either. I did a practice run with just water and was able to hit and hold target temps in the space of ten minutes or so a piece. I was able to get to a rolling boil with just water pretty quickly as well.

Even accounting for it being slower with grain this time, I've had the temp dial turned to 110 for a full hour trying to get my temperature to 67c and its gone from 56 to 62 in that time. It won't go up from there. The light keeps blinking on and off every few minutes. Fairly sure the beer is a goner at this stage as its been sitting for way too long at this random temperature and just won't go any higher. Was hoping to do a step mash.. I've done about a step and a half :( Any ideas on what I'm doing wrong or how to fix?
 
Have you raised the bag? And what are you using to measure temp?
 
It is new, but I guess my thinking is that it boils water exactly as it should, so its likely I'm just doing something wrong now that the mash is involved. I'm circulating it with the paddle a bit to keep cycling wort past the heating element but this doesn't seem to help. Would like to avoid returning it until I'm sure there's a defect as I'd have to courier it back to the source up north.
 
bradsbrew said:
Have you raised the bag? And what are you using to measure temp?
Good thoughts! I'm using a digital and floating thermometer to measure temp. Same as I used when I did a practice run with water. I've tried raising the bag but it didn't trigger the heating after a half minute of holding it there. Might try holding it up a little longer and stirring.
 
It is new, but I guess my thinking is that it boils water exactly as it should,
Hmm.. maybe I should have read your first post properly!!!
 
pnorkle said:
Hmm.. maybe I should have read your first post properly!!!
Haha you're all good man. I might still get to that conclusion anyhow. I'm just banking on my own incompetence being the more likely cause.

I've wrapped it in a towel as I'm running out of ideas and that's humorously brought it up to the 67 degrees i was aiming for. Doesn't seem to want to move beyond that at any great speed but maybe lifting the bag in and out might help it along. Not a sustainable solution really though. Would love to know what the heck is going on. The little pilot light still keeps blinking in and out every few minutes. Will see if i can get it up to the 76 or whatever I need before the sparge and then hopefully the boil should follow at some nearby point in the future with the heater maxed out. Fairly sure all this stirring and extended mash time won't do me any favors but then this kind of stupidity is what the first few goes is all about right? :/
 
Sparged at about 75c and packed around it with towels and its just sitting at 72c and going up a couple of degrees an hour. Super frustrating. Probably just have to pour it out. Must be a broken thermostat or something? Maybe it worked the first time and then started faulting this time around. Sitting on 30l of wort with no means to boil it. Feels bad :(
 
Have you tried turning it off, pressing the reset underneath then turn on again?
Near boiling water would have been a good sparge, to bring the total temp up.
 
Sounds like a faulty thermostat, i use a crown urn concealed element and never had an issue. As im sure many others do too. My money is on you have scorched and burnt grain onto the element. Only issue i ever had was with Rye scorching and covering the element making the thermostat turn off stopping the boil.
 
Try to scrape the element with something long.

It sounds like the thermal cutout not the thermostat.
 
raise the bag and drain and see if it will boil* what you have.

* maybe dump the wort into something, check the inside of urn for scorching and the tip back in and boil
 
Maheel said:
raise the bag and drain and see if it will boil* what you have.

* maybe dump the wort into something, check the inside of urn for scorching and the tip back in and boil

Markbeer said:
Try to scrape the element with something long.

It sounds like the thermal cutout not the thermostat.

Drewski said:
Sounds like a faulty thermostat, i use a crown urn concealed element and never had an issue. As im sure many others do too. My money is on you have scorched and burnt grain onto the element. Only issue i ever had was with Rye scorching and covering the element making the thermostat turn off stopping the boil.
Well spotted everyone. I drained the wort and the plate is scorched to hell :eek: I've applied elbow grease and bicarb and its back to how it should be. tested a little bit of water and it boiled nicely. Whew! No RMA on my horizon. This does leave me with two questions though

1.) Can I tip my wort back in to start the boil? I threw it all into a cleaned fermenter to sit. Its been aerated a fair bit now though as a result and the mash was on for a good two or three hours at a range of exciting and exotic temperatures not quite including 77c. It will have cooled a bit. Maybe I should put it back on just for science. I had a little yeast starter going and everything.. I'm guessing it'd be more of a Burned Cardboard Ale now..
2.) How the heck does one avoid a buildup of trub like this in the strainer? I'm not sure how anyone would go about circulating fluid through there, but this must obviously be done somehow. I'd have thought just stirring inside the bag near the base would be enough to whip things around, but this doesn't appear to be so?

Attached are exciting pics of the grim aftermath and the strainer in question

gunk container aparantly.jpg
el schorcho.jpg

bradsbrew said:
Have you tried turning it off, pressing the reset underneath then turn on again?
Near boiling water would have been a good sparge, to bring the total temp up.
I'd considered using near boiling water for just that reason! though I don't know enough about the chemical processes yet to start experimenting. Regardless though with the element a mess I dont think it would have helped sadly.
 
You've got exactly the same set up as me, I've never had this scorching build up though. I can see you've also got the false bottom so that should be keeping the bag well clear. What grains are you using?
 
What temperature did you actually start the mash at? With urns I found that you really need to get your strike liquor temperature such that you go straight into a sacch rest, then lag the urn and leave it switched off. Then you can switch on and ramp up to do a step mash or a mashout if you wish (Hochkurz Mash for example).

However starting low (say about 52 degrees for a protein rest) there is a lot of unconverted "free" flour that sticks then burns onto the element.

You can always do a protein rest in an urn using BIAB, just start with a thicker mash and raise to sacch rest temperature with boiling water addition.
 
Maybe that's why I've never had this problem then, I don't step, and I get up to temp first?
 
Yup. I've done only single infusion mashes at around 66 degrees for a couple of years now and had consistent results with all styles.

Edit, I had a quick squiz at the Probrewer forum where US pro micro dudes hang out and the jury is out on step and mashouts, especially when using modern malts.
 
stir the mash the whole time the element is on, if you want to prevent scorching.
 
Maybe next time you could put something under the side of the urn to give it a slope to minimise anything settling on the element during steps.
 
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