Recirculating cooled wort back into the kettle.

[Beerisyummy]

Hi all,

Of late, I've been using a brown pump to run boiled wort through a CFC and it seems to struggle with cooling the deadspace in the pot.

I haven't taken readings of the wort exiting the CFC, but the wort is around the 35-40c mark after one pass. A tepid bath, is the words I would use to describe the touch.

My problem is that it seems to take a long time to get the temps down, even though the CFC is doing it's job quite well.

On my last brew I had adjusted the inlet to get good mixing flow in the kettle( again) and noticed the pot itself was holding a massive amount of heat. So much so, that I could scold my inner forearm on the section of the pot above the liquid level.
Below that level was all good.

Does anyone have any suggestions for getting the kettle and deadspace down to temps quickly, without opening the lid and introducing nasties?
I considered buying a plate chiller but don't think it would do much better.

Cheers
Ross.

 

[woodwormm]

bearing in mind, I'm still in design phase with my system... so my suggestions are with a large grain of salt...

have you considered chilling the water going into your CFC? Things like CFCs and Plate Chillers will all have their own maximum efficiency based upon what they're given to work with.. ie they'll cool a certain number of degrees down relative to hot liquid temp and cold liquid temp.

so if you can lower your cool liquid temp by chilling it through an ice bath before the CFC, it should help a lot, also it you can know a few degrees off kettle temp by waiting 10 or 15 minutes this may help too...personally i'd do it with lid off as i'm pretty sure 100-80 ish degree wort will kill any nasties but it's in your tepid range you want to be careful...

 

[Beerisyummy]

bearing in mind, I'm still in design phase with my system... so my suggestions are with a large grain of salt...

have you considered chilling the water going into your CFC? Things like CFCs and Plate Chillers will all have their own maximum efficiency based upon what they're given to work with.. ie they'll cool a certain number of degrees down relative to hot liquid temp and cold liquid temp.

so if you can lower your cool liquid temp by chilling it through an ice bath before the CFC, it should help a lot, also it you can know a few degrees off kettle temp by waiting 10 or 15 minutes this may help too...personally i'd do it with lid off as i'm pretty sure 100-80 ish degree wort will kill any nasties but it's in your tepid range you want to be careful...

I have considered chilling the cooling water. It wont work on this one.
To be totally honest, I think a tall thin boiler woud fix the problem.

Maybe I need to add a cooling jacket to the list of things to build.

 

[dr K]

Does anyone have any suggestions for getting the kettle and deadspace
down to temps quickly, without opening the lid and introducing nasties?

Are you boiling under pressure? A sort of pressure cooker method...
Otherwise why have a lid, apart from the early part of the boil where a lid may speed things up you really should not cover your boil (google DMS).
That aside you make a good point.
I use a whirlpool immersion chiller set up (based on the Jamil model) and was talking only the other day to a brewer who was thinking of using a plate chiller whirlpool combination. This makes great sense as the pump will rapidly recirculate the wort and the whole of the wort, rather than only that passing through your plate chiller will be cooled quickly.
Of course a Brown Pump, great as they are will not have the power to do this.
Magnetic Drive 240V polysulphone impeller pumps (March pump alternatives) are widely available in Australia, often at less than $100. This is the way to go, one pump (with a bit of hose changing) can do your fluid movement from filling the mash tun from the HLT to whirlpooling and cooling your wort, it can even run yours RIMS if you get really serious!

K

 

[Beerisyummy]

Are you boiling under pressure? A sort of pressure cooker method...
Otherwise why have a lid, apart from the early part of the boil where a lid may speed things up you really should not cover your boil (google DMS).
That aside you make a good point.
I use a whirlpool immersion chiller set up (based on the Jamil model) and was talking only the other day to a brewer who was thinking of using a plate chiller whirlpool combination. This makes great sense as the pump will rapidly recirculate the wort and the whole of the wort, rather than only that passing through your plate chiller will be cooled quickly.
Of course a Brown Pump, great as they are will not have the power to do this.
Magnetic Drive 240V polysulphone impeller pumps (March pump alternatives) are widely available in Australia, often at less than $100. This is the way to go, one pump (with a bit of hose changing) can do your fluid movement from filling the mash tun from the HLT to whirlpooling and cooling your wort, it can even run yours RIMS if you get really serious!

K

Thanks for the reply. All points taken over time as I truly understand them.

No pressure involved in the kettle. I have been leaving the lid on after the boil to limit airborne contaminants.
Is it worth the bother?

 

[bradsbrew]

without opening the lid and introducing nasties?


Cheers
Ross.

Otherwise why have a lid,

I put a lid on the kettle right after whirlpool to avoid nasties landing in the kettle.

 

[Cocko]

I put a lid on the kettle right after whirlpool to avoid nasties landing in the kettle.

Same.

I have NEVER had an infection... to date.


Touching my wood.

F7Ck, now cursed yeah?

Nope.

 

[Beerisyummy]

Touching my wood.

Now I'm pretty sure you meant to say "touch wood". At least I hope so.

I looked into whirlpool chiller combos and that's pretty much where I'm headed. Given that I'm only using a 50l SS pot with around 25-30l post boil, the brown pump should be enough to get the bulk moving over half an hour.
If not I'll look into those bigger pumps you mentioned K.

I always figured the stainless would cool down fairly rapidly once the wort was cooled. Next brew I'll just leave the lid off while cooling down the wort. It just made sense to leave it on if possible.

 

[booargy]

I had a fixed immersion chiller coil in my 18G keg and used a whirlpool inlet on the keg. I have changed over to a plate chiller which works just as well. But what I have been thinking it to start using an immersion chiller as well as the plate.
I circulate through the plate chiller and in back into whirlpool inlet at start of boil for 10-15mins. The timer starts when roiling boil is maintained.
10min to end of boil start recirc through plate chiller.
At power off run tap water through immersion coil and pate chiller recirc until entire wort reaches 80c or lower depending on pitch temp.
once at <80c run off wort to fermenter through plate chiller(cooled with iced water) to pitch temp.

The main advantage I can see of doing this is your wort is dropped very quickly to 80c due doubling the cooling capacity. And the temp can be dropped so less ice water is needed.

 

[MastersBrewery]

I'm sure I've read somewhere when using a CFC it is less efficinent to return cooled wort to the kettle; possibly on HBT or here

 

[Malted]

Touching my wood.

Now I'm pretty sure you meant to say "touch wood". At least I hope so.

Nope he said what he meant to say. He was having fun playing with the words, or himself... At any rate we're all now cringing because we thought about his wood. His mission is accomplished.

I have seen his wood, he has a big deck that I think he erected himself. His missus loves sitting on his deck, I have seen her do it; she used both hands so she wouldn't fall off. Just between you, me and the interwebz, I think the dog likes sitting on Cocko's deck too but can't be sure about that because I only saw it lick the parts underneath his deck.

 

[Beerisyummy]

I had a fixed immersion chiller coil in my 18G keg and used a whirlpool inlet on the keg. I have changed over to a plate chiller which works just as well. But what I have been thinking it to start using an immersion chiller as well as the plate.
I circulate through the plate chiller and in back into whirlpool inlet at start of boil for 10-15mins. The timer starts when roiling boil is maintained.
10min to end of boil start recirc through plate chiller.
At power off run tap water through immersion coil and pate chiller recirc until entire wort reaches 80c or lower depending on pitch temp.
once at <80c run off wort to fermenter through plate chiller(cooled with iced water) to pitch temp.

The main advantage I can see of doing this is your wort is dropped very quickly to 80c due doubling the cooling capacity. And the temp can be dropped so less ice water is needed.

Do you mean 80F?

I do like the idea of cooling things down quickly. I usually use the run off to do a heap of the cleaning tasks and fill a few buckets so I'm not wasting water, just time.
Maybe I should've held onto my 1/4 hp aquarium chiller. That sucker would have chilled things down pretty quickly.
Come to think of it I still have a smaller unit floating around in the garage that I could use to feed the CFC once it hit below 40c. It might work and won't hurt to try.

 

[Beerisyummy]

I'm sure I've read somewhere when using a CFC it is less efficinent to return cooled wort to the kettle; possibly on HBT or here

Yeah, I think you're right there.
Once upon a time I made up a spreadsheet for working out dilution rates with daily pollution inputs that would fit the bill with a few mods. At the time I was trying to work out the loss in efficiency due to lots of small water changes using a dosing pump, compared to larger and less frequent batch changes.
The results were surprisingly minimal over time, but nothing beats totally removing 100% of the volume. Especially when the heat of the pot seems to hold so much energy.
7kg of stainless will do that I guess.

Maybe my methods are flawed?

When people whirlpool, does the wort need to be fully cooled to ptching temps for any reason? I had assumed that less surface agitation and better trub settlement were the aim.

I guess I'll just have to brew another batch soon.

 

[Beerisyummy]

Nope he said what he meant to say. He was having fun playing with the words, or himself... At any rate we're all now cringing because we thought about his wood. His mission is accomplished.

I have seen his wood, he has a big deck that I think he erected himself. His missus loves sitting on his deck, I have seen her do it; she used both hands so she wouldn't fall off. Just between you, me and the interwebz, I think the dog likes sitting on Cocko's deck too but can't be sure about that because I only saw it lick the parts underneath his deck.

I play with wood all the time.
This bloke's playing with another guys wood that I was payed to work and mount, although the quote said supply and fit.
To top things off, the original guy's wife told me I had done an amazing job when installing the wood in her unit. I showed my wife some pictures of the event and she complimented me on a great job too.

 

[Beerisyummy]

[sharedmedia=gallery:images:7214]

Website gremlins messed with the photo in the last post.

 

[dr K]

Beerisyummy
I assumed from the topic and your initial post that you were running your hot wort through a CFC and back into the kettle.
Is this what you do?

K

 

[Beerisyummy]

Beerisyummy
I assumed from the topic and your initial post that you were running your hot wort through a CFC and back into the kettle.
Is this what you do?

K

Yeah K. Spot on.

The plumbing coming out of my kettle splits into two taps. One for the drain hose and one for the pump.
From the pump I have another two taps. One short efficient run for recirculation and the other one runs through the CFC.
I have been running the hose from the CFC back to the kettle during cooling.

My routine for the last few brews goes something like this.
Add insulation jacket and lid to kettle and crank up the induction cooker.
Once the boil starts I run the hot wort through the plumbing for 5mins then remove the lid once it boils again.
Ten minutes before the end of the boil I start running hot wort through the plumbing again.
As soon as the boil is done I turn off the cooker, remove the insulation jacket and turn on the cold water tap to let the CFC do it's thing.
Once the wort has cooled down to 25-30c I take off the lid and give it a big whirl( the wort not the lid ).
The lid goes back on and I leave it for ten minutes then drain into the FV.

 

[MastersBrewery]

I can see good reason to return to the kettle, in regard to hopping around the 80c mark for a flavour kick (say 10 min), beyond this it's quicker and uses less water to CFC to fermenter control the flow of wort to control temp.