Recirculating HLT Design

[Fat Bastard]

For those of you with a recirculating HLT, do you just dump the water back into the top of the tank or do you have a whirlpool arm arrangement to take the water back down below the surface? Currently mine just dumps back in via an elbow, but if necessary can modify it to go to the bottom of the tank. Is HSA even an issue with water?

Also, where do you have your probe? Mine is plumbed into the recirc system just below where it returns to the tank, abou halfway between the bottom of the tank and the mash tun. My HLT is below the MLT as a space saver.

Your thoughts on this would be appreciated.

Cheers,

FB

 

[leahy268]

I just dump it back in to the top myself.

As far as the probe goes I just have it in the middle of the pot. I have moved the manual thermometer around when its recirculating though and haven't found any cold spots.

 

[southcoastbrewer]

HSA, ahh, lol, read so much on this, and you know what i have decided its a myth... mine runs through the rotating sparge arm... so its raining back into it... itll be fine....

Southcoast

 

[Yob]

A myth it's not, but if you try really hard you can get there...

Many points here but if you are going the recirculating route... As I did.. Look into HERMS, without heating the flow you will drop temps quickly, once you have a hex, set, forget... It's like the brew fridge of mashing

 

[spudfarmerboy]

A myth it's not, but if you try really hard you can get there...
Many points here but if you are going the recirculating route... As I did.. Look into HERMS, without heating the flow you will drop temps quickly, once you have a hex, set, forget... It's like the brew fridge of mashing

He is talking about recirculating on his HLT, not his mash.

 

[MartinOC]

I recirculate back into the top with a copper "U" bent copper elbow. My probe sits at the bottom of the tank, submerged with a spare bit of SS I had left over from the initial build.

Wally, yes, the reason for doing this is to get homogenised temperature within the HLT. I found that if I just have the HLT element on with no recirculation, there can be as much as 10-15C difference between the bottom & the top.

 

[hotmelt]

FB,

I've tried a search, but have not come up with anything.

Please explain why you are recirculating in an HLT?

Are you trying to achieve an homogenous temperature in the HLT?

See Gava's build picture.
http://aussiehomebrewer.com/topic/42248-brew-rigs/page-50#entry1156310

 

[mb-squared]

For those of you with a recirculating HLT, do you just dump the water back into the top of the tank or do you have a whirlpool arm arrangement to take the water back down below the surface? Currently mine just dumps back in via an elbow, but if necessary can modify it to go to the bottom of the tank. Is HSA even an issue with water?

Also, where do you have your probe? Mine is plumbed into the recirc system just below where it returns to the tank, abou halfway between the bottom of the tank and the mash tun. My HLT is below the MLT as a space saver.

Your thoughts on this would be appreciated.

Cheers,

FB

Hi FB, the only reason (as far as I can tell) to recirculate the hot water in the HLT is to keep a uniform temp throughout the pot. Perhaps a return tube that produced a whirlpool would be best, but simply returning the water to the top of the pot should be sufficient to keep the water moving and to give thermal dynamics a chance to take care of the rest.

As for where to put your temp probe, it depends on what you have. I have mine in a short thermowell that fits in a stainless "T" on my output valve. That way I am taking the temp right at the point where the water is exiting the HLT. If you read the temp at the point the water is *entering* the HLT, then you'll be reading a cooler temp than the water in the HLT. Probably not a good place to be reading the temp, especially if you have a HERMS coil sitting in your HLT. If you have a long thermowell that you can put into the side of your HLT, then you'll want to put it low enough that it will always be submerged, even on your smallest of batches.

Cheers,

 

[Yob]

He is talking about recirculating on his HLT, not his mash.

aah, my bad..



Heres an older HLT but my new one is essentially the same

 

[Fat Bastard]

This took a while to get going but get going it certainly did!

I have to pump up to the MLT anyway, so the pump is already there, and avoiding stratification in the tank is probably no bad thing. The tank is overly large at 80l for my little 36/23l system, but the idea is to heat excess water so I can get the MLT & HX recirculating with PBW while boiling.

I'm currently commissioning the beast and having the probe plumbed into the recirc system seems to be working just dandy. I'll post up some pics later. Temp on the calibrated dial thermometer seems to be within half a degree of the temp controller, so I guess it's close enough for now.

Cheers all!

FB

 

[Fat Bastard]

Pic of the inside of the HLT

The return is at the top left of the pic. One thing I found, is that unless the tank is absolutely brimming full, it sounds like a racehorse pissing in a bucket. Small potatoes really, but will be on the list of things to fix when I get around to it.

The temp control readout does lag behind the thermometer, but equalises very quickly after temp has been reached. Not surprising the thermometer is diectly above the element. Pretty pleased with how it works, I'm about to start a new thread on my fancy new rig, so I'll post up further pics there.

Cheers!

FB