What kind of pump?

[azazel1024]

Right now I just have a basic immersion chiller with some 1/2" ID tubbing on it (3/8" coiled copper immersion chiller). It works great at home/for ales. I am kind of lucky that my ground water is as cool as it is for my well, as in the winter time the outlet temp is around 52F and in the summer it is still only up around 56F. Still takes a LONG time to get near lager temps, but down to 65-70F is very fast (maybe 5 minutes from a boil down to 120F, 5 minutes from 120F to 90F and maybe 10 minutes from 90F to 65F). The 1/2" tubing clamped to the 3/8" immersion chiller is because I use it in my kitchen sink and I basically have to pressure fit the 1/2" over the connection for my sink sprayer, which works perfectly as it just pushes over it once I unhook the sprayer with nary a leak.

Two things I am looking at doing is upgrading this so that I can both hit lager temps better/faster and also so that I can take this "on the road" easier for away brew days (where I don't necessarily always have a garden hose).

So I was thinking of getting a second basic immersion chiller like my current one. When I need to hit lager temps, for the end of the cool down, drop it in a small pot/bucket of ice water and run the tap water through the ice bucket coil first and then in to the brew pot. In most cases I am only looking at getting an extra 5-10F of cooling and also getting there from 70-80F a few minutes faster. So I think this will work.

However, I ALSO want to be able to cool on the road without a source of ready water to flow through the immersion chillers. So I was thinking recirculating pump that can operate on a 12V deep cell battery of smallish size (like a 6-12Ah battery). Then use a single immersion chiller to pull water from the ice bucket, run it through the immersion chiller and then back in to the bucket. I've seen some setups like this in the past, but I've never asked/figured out what kind of pumps are used.

I've gotten a suggestion from someone to just use a sump pump, but a 1/4-1/3hp pump seems like MASSIVE overkill. I was thinking a GOOD aquarium pump that can operate on 12v and is probably more in the range of 1/20-1/10hp (35-70 watts) is probably enough flow rate, preferably that has either 3/8" or 1/2" inlet and outlet.

Would this be sufficient? Would it be WAY undersized? Any good, reliable suggestions? Something that can operate either straight on 12v battery or through a 12v power adapter would be nice too.

Thanks!

 

[thekraken]

I recirculate ice water with a cheapo submersible pump from harbor freight: http://www.harborfreight.com/lawn-garden/pumps.html
The one I have operates off of 120vac, not sure if they have 12vdc versions or not.

Others could chime in on this but I'm not so sure that the second pre-chiller coil is very efficient, just pump/recirculate that 32F ice water itself.

(edit) you could always use one of these little guys for a 12v pump: http://www.amazon.com/gp/product/B00DWORE5A/?tag=skimlinks_replacement-20

They would just require a little more set up and aren't self priming.

 

[BrotherBock]

I recirculate ice water with a cheapo submersible pump from harbor freight: http://www.harborfreight.com/lawn-garden/pumps.html

This works well. I recently brewed with some friends, they had a pump and we hooked it up to my chiller. We put the pump in just a couple gallons of water then filled the bucket with snow. As the snow melted we filled it with more and drained of the excess water. All in all we only used 2 gallons of water from the tap to chill and just used snow. It worked real well and wasted the least amount of water I've ever used for chilling.

Obviously not an option for everyone. Winter brewing is great.

 

[Photopilot]

Agreed on a smaller pump. Anything cheap at harbor freight or a medium sized pond pump at Lowes or Home Depot should suffice. Stay away from 12V bringing a battery into the mix is just another level of complication to avoid.

 

[azazel1024]

Well, the 12v operation was so that all I'd need to do is haul a battery to a brew, but I guess when it comes down to it, most brew events I've done have had garden hoses and outlets that could be used.

I'll check out the 265GPM harbor frieght unit. It looks right sized for what I'd probably do (that and a 6G bucket from home depot filled with some water and a bag of ice I'd imagine should do the trick).

Probably keep using tap water most of the time, it is cheaper than a bunch of ice, but do a recirc in a large pot with a couple of trays of ice and some water once I get in to the 70s and want to drop it down to lagering temps.

Thanks!

 

[thekraken]

I use tap water until the temp drops below 100 degrees F then I switch to recirculating with ice water. There is a ice house vending machine nearby that I buy like 22lb of bulk ice for $2.

Something to keep in mind: I use about 20 gallons of tap water before I start recirculating ice water, that tap water goes into 5gal Home Depot buckets and saved for reusing in my next couple loads of laundry. I imagine if you don't have a way to reuse this water it would be a very wasteful method of chilling, and if you recirculate the whole time it would take much longer to chill.

 

[azazel1024]

I use tap water until the temp drops below 100 degrees F then I switch to recirculating with ice water. There is a ice house vending machine nearby that I buy like 22lb of bulk ice for $2.

Something to keep in mind: I use about 20 gallons of tap water before I start recirculating ice water, that tap water goes into 5gal Home Depot buckets and saved for reusing in my next couple loads of laundry. I imagine if you don't have a way to reuse this water it would be a very wasteful method of chilling, and if you recirculate the whole time it would take much longer to chill.

I have the advantage of living in a pretty wet area of the country with a very shallow well (~60ft). I could of course run it dry some year, but I suspect not as the central Maryland area is getting wetter if anything over the last few decades (upside to climate change?).

That said, based on my flow rates and a rough guess without capturing the water, for a 4-5 gallon batch based on how often my pump has to run to refill my pressure tank and pressure tank size, I'd say I run probably 20 gallons if I take it from boil to 75-80F. I generally leave it full blast till it hits 120s and then turn down the flow rate to maybe 75%, and then to about 50% once it hits below 100F.

Clocking it, it takes maybe 1-2 minutes longer to hit mid 70's by doing this, but uses about 50% of the water in the end.

If I was in a drought area, I'd probably save the water to reuse in something else. If I can get it down in to the mid-70's I figure an 8qt pot with a couple of trays of ice in it with recirculation should probably be enough to pretty quickly push the temperature down to the high 50's, which I figure is probably a good pitching temp for lager yeast and then let the fridge take it down the extra 4-8F to proper fermentation temperature over a couple of hours.

 

[thekraken]

I would have thought it would take more than a couple trays of ice to have a real impact. But I haven't tried that before so please report back and let me know how well it works. What is the temp of your tap water?

 

[azazel1024]

I would have thought it would take more than a couple trays of ice to have a real impact. But I haven't tried that before so please report back and let me know how well it works. What is the temp of your tap water?

Summer time, if it is fresh from the well, about 58F, in the winter time it is closer to 53F. A couple of trays of ice in a 6qt pot with some tap water in there is probably closer to 40F in a few minutes.

Don't need it to push 100F temps down, just say 80F temps. Even though the volume is a lot less, that should hopefully be enough to take it down another 20F.

If it proves not to be enough I can always toss in some freezer cold packs, or freeze a 2qt jug and stick it in the pot with the water and ice cubes.