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Kirk Gittings
21-Aug-2016, 14:38
Guys. I tend to develop film once or twice a year in marathon sessions as I have no real deadlines to meet with my film photography. These sessions are almost always in the winter when the water temperature is low or at least lower than 68 degrees. For reasons that are not important I could not develop film this last winter and need to do it now or soon. Tap water right now is like 78 degrees. Doing the odd sheet of film by chilling down the chemicals is one thing. Doing it for a solid two weeks for 400 sheets of film, 6 at a time, is another level of PITA all together. Is there a cheapish ($100) water chiller option over the counter that works? Or if not a DIY option that I could build?

Jac@stafford.net
21-Aug-2016, 14:57
Kirk, you got my attention but I have no inexpensive solution, but I do have a question - do you have an old well on your property? I ask because when I lived in New Mexico a great find was a well that failed. Failed to continue delivering water, but at the deepest part it was cool and dropping a coiled up lawn hose fed by city water then back up was a treat.

Thinking, thinking..

Best of luck, Sir.

interneg
21-Aug-2016, 15:13
My immediate suggestion would be a wort chiller/ immersion chiller/ heat exchanger - they can be had from brewshops/ brewing suppliers for under $100 for a smaller model & work very well indeed. However they do need a source of cold water to be pumped through them. I guess you could use one 'backwards' as it were - sit it in ice/ chilled water & pump the water you want to cool through it, but I'm not sure how well that would work.

Pere Casals
21-Aug-2016, 15:14
Guys. I tend to develop film once or twice a year in marathon sessions as I have no real deadlines to meet with my film photography. These sessions are almost always in the winter when the water temperature is low or at least lower than 68 degrees. For reasons that are not important I could not develop film this last winter and need to do it now or soon. Tap water right now is like 78 degrees. Doing the odd sheet of film by chilling down the chemicals is one thing. Doing it for a solid two weeks for 400 sheets of film, 6 at a time, is another level of PITA all together. Is there a cheapish ($100) water chiller option over the counter that works? Or if not a DIY option that I could build?

I understand you only need to control developer temperature,

I've similar problem in summer, but as I use Xtol 1+1 I mix cold water that was stored in a chiller with stock developer, if developer is at 74º I prepare cold water at 62º (or 61) when mixing 1+1 the resulting temperature will be 68º. Stop bath and fixer temp it's a least concern...

If you develop with stock solution you have de possibility to store part of the developer in a chiller (at say 55ºF) and then mixing it with developer at room temperature until you get 68º.

Kirk Gittings
21-Aug-2016, 15:14
Thanks but no Jac. I like the idea. We live in the city in an area that hasn't had legal wells probably since the 50's. When I bought the property in 76 there was an old well pipe but since it wasn't legal and probably dry (the water table has dropped from the city wells) we cut it off, capped it, and buried it.

LabRat
21-Aug-2016, 15:30
Being in the SW, you should consider a water line chiller... (Think of it as an air conditioner for your water) Even if it's a low flow unit, you can use an old water heater as a holding tank after the chiller so you have a a steadier cooled reserve for extended flow, such as washing... Some with a thermostat can reverse the cycle and be used to warm the water during winter months, so another benefit...

Or you can wait a few weeks and everything should cool down by then...

Steve K

Kirk Gittings
21-Aug-2016, 15:46
Being in the SW, you should consider a water line chiller... (Think of it as an air conditioner for your water) Even if it's a low flow unit, you can use an old water heater as a holding tank after the chiller so you have a a steadier cooled reserve for extended flow, such as washing... Some with a thermostat can reverse the cycle and be used to warm the water during winter months, so another benefit...

Or you can wait a few weeks and everything should cool down by then...

Steve K

Thanks. They are pretty pricey though right?

Luis-F-S
21-Aug-2016, 16:01
Why I have an Elkay erw 32 chiller but it's a lot more than $100 by a factor of around 15x.

LabRat
21-Aug-2016, 16:20
Thanks. They are pretty pricey though right?

I ended up with one several years ago, that I didn't get around to hooking up... My was from scientific surplus, a high flow model, but very heavy (150lbs + on wheels) that was probably used as a part of a laser cooling water jacket assy, and had a thermostat dial for cooling + heating + requires a 240 VAC line... In short, it is probably overkill, but an industrial grade unit, but was about $150 surplus...

But it made me look around on line to see what else was out there, and there are several lower output units that were very reasonable and smaller for I think lower than a few hundred dollars, but were slightly heavy (but smaller) but the shipping costs were a factor... But there might be a lab or medical gear supplier in your area that have them new or surplus... Google them and see if they might be an option... Sure would be the greatest darkroom thing since sliced bread!!! (At least a small one might be used as a water jacket in a sink, but enough flow for a warm water line use would be a question to ask...)

Steve K

Eric Woodbury
21-Aug-2016, 16:47
Kirk, Is the darkroom air conditioned. Developing film in warm air and cool water is a moving target. Turn on the AC to have a comfortable darkroom, freeze some milk cartons that you use to chill trays and graduates, etc., with cool water. 72F to 75F chemicals are fine and don't really need anything special. Follow the temperature charts and off you go. If you don't have AC, do you have a swamp cooler? The water in the basin of my swamp cooler is quite nice. You could cool off your chems there. If all you have is heat, wrap your chem bottles in a towel and blow a fan across them. Keep the towels wet. Like an old water bag on the front of the car or fence post.

There's a water chiller on Craigslist in ABQ for $300. That money would buy a lot of ice.

Kirk Gittings
21-Aug-2016, 20:05
I just found one of these for $50. I'll see if I can make that work. For the price it's worth a try. https://www.amazon.com/Oasis-Water-Chiller-Refrigerated-Under/dp/B00ESISVCY

LabRat
21-Aug-2016, 21:27
I think that would work for a water jacket, but a low flow for washing, etc... If you used it to fill a tank, then used gravity for feed, you can work it out I think... (I'm expecting the flow output of a water fountain...) The industrial one I have has a strong recirculating pump, but maybe that's not needed...

I think it has possibilities, and worth a try...

Steve K

Roger Thoms
21-Aug-2016, 22:46
I just found one of these for $50. I'll see if I can make that work. For the price it's worth a try. https://www.amazon.com/Oasis-Water-Chiller-Refrigerated-Under/dp/B00ESISVCY

1 GPH, gallon per hour? Sounds to low for darkroom use.

Roger

IanG
22-Aug-2016, 05:40
There's been other threads on this subject. When I'm in Turkey I process all my films 27ºC (just over 78ºF) the summer water temperatureand it's far easier than rying to chill chemistry. We don't have space for a chiller anyway. There's no difference in quality at all between negatives processed at 27ºC or those I process in the UK at 20ºC.

If you want a simple very cheap DIY chiller take a working home fridge apaprt and use the chiller unit & compressor etc - place the chiller in a small tank of waterand run it to almost freezing. I made one this way in the 1970's, I needed water at <2ºC for emulsion making (washing) it worked brilliantly for over a decade and took up very little room, it was fed with deionised water.

Ian

Kirk Gittings
22-Aug-2016, 07:17
I think that would work for a water jacket, but a low flow for washing, etc... If you used it to fill a tank, then used gravity for feed, you can work it out I think... (I'm expecting the flow output of a water fountain...) The industrial one I have has a strong recirculating pump, but maybe that's not needed...

I think it has possibilities, and worth a try...

Steve K

It may not work but it is cheap. I'm not worried about washing temp. I just gradually raise the temp of the after fix rinse tray and then put them in the film washer at ambient temp.

Kirk Gittings
22-Aug-2016, 07:22
There's been other threads on this subject. When I'm in Turkey I process all my films 27ºC (just over 78ºF) the summer water temperatureand it's far easier than rying to chill chemistry. We don't have space for a chiller anyway. There's no difference in quality at all between negatives processed at 27ºC or those I process in the UK at 20ºC.

If you want a simple very cheap DIY chiller take a working home fridge apaprt and use the chiller unit & compressor etc - place the chiller in a small tank of waterand run it to almost freezing. I made one this way in the 1970's, I needed water at <2ºC for emulsion making (washing) it worked brilliantly for over a decade and took up very little room, it was fed with deionised water.

Ian

Here is why I don't want to do 78 degrees. Too short dev. times. Yes I can dilute it further but not with BTZS tubes as the dev. volume is too small to dilute. I like the idea of stripping a small fridge and have one out back. I also have a spare small window air conditioner I could adapt.

Kirk Gittings
22-Aug-2016, 09:37
I think that would work for a water jacket, but a low flow for washing, etc... If you used it to fill a tank, then used gravity for feed, you can work it out I think... (I'm expecting the flow output of a water fountain...) The industrial one I have has a strong recirculating pump, but maybe that's not needed...

I think it has possibilities, and worth a try...

Steve K

Here's what I think I'll try. I will get a small tub for a tempering bath. I'll put a small submersible aquarium pump in it, hook it up to the inlet side of the chiller to push water into the chiller and run the chiller outlet back into the tub.

bob carnie
22-Aug-2016, 10:28
Send the film to Canada its always cold up there.

CedarMesaPhoto
22-Aug-2016, 10:35
I had a big mid-summer commercial project once that involved using several five gallon buckets and some bags of ice to make really cold water, which I then used to mix with tap water to make my chemicals. My tap water is cooler in the morning than later as well, so I plan for that for washing. I have only done that once, usually a couple gallon jugs in the fridge is enough to mix with.

Sent from my XT1080 using Tapatalk

Michael Mutmansky
22-Aug-2016, 11:52
Someone above mentioned a wort chiller, and that's exactly what I would do for the occasional use like this...

Here's a photo of what they look like:

https://www.google.com/search?q=wort+chiller&rlz=1C1ZMDB_enUS561US561&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi95O6h1tXOAhXKkh4KHTHyBiYQ_AUICigD&biw=1731&bih=898#imgrc=LqE-K9X3MKz00M%3A

You can put one in an insulated ice cooler and supply chilled water to your DR all day long with a bag or two of ice.

Depending on the flow, it would be easy to get 50 degree water out of something like this, even much cooler, so you can then set the cold/hot mix exactly where you want it. Keep feeding ice in as the ice melts, and you will have a fairly steady flow.

Since it is for the occasional use, this would probably work better and you can put it in storage easily when not needed.

You can make one by getting 1/4" or 3/8" flexible copper tubing at the home center and coil it to fit whatever you want to put it in, and then put some flared or compression connections on the ends to connect it to your water supply at the sink and then to the Jobo or whatever you are connecting it to.


---Michael

bob carnie
22-Aug-2016, 11:58
Kirk- what is the ambient room temp in your darkroom? , we leave water in tray overnight to settle to room temp, its usually around 70degree year round, this way the water is always right temp for developing.

Jason Greenberg Motamedi
22-Aug-2016, 12:58
My solution to this was to pull a water cooler (like this one (https://www.amazon.com/Oasis-International-504336C-Countertop-Cooler/dp/B002WDNXD4/ref=sr_1_7?s=kitchen&ie=UTF8&qid=1471895516&sr=1-7&refinements=p_n_feature_keywords_browse-bin%3A7492376011%2C5901203011)) out of a dumpster at work. It cools the water down to about 15*C, and I just mix the cool water with the warm water from my tap. If this were an going problem for me (its only a month or two of summer here) I would probably rig up some sort of digital temperature controller to dispense the cool water, sort of a DIY sous vide (do a search) in reverse.

blindpig
22-Aug-2016, 13:29
Kirk.
Long ago a studio I worked for had the same temperature problem you are describing and my boss was concerned about the cost of a chiller unit.We found a remote drinking fountain cooler( the porcelain bowl on one side of a wall and the cooler on the other side) at a place that salvaged building materials pretty cheap.The problem was the tank only held 4 to five gallons of water which was solved by talking a local heating and air conditioning company out of a damaged 40 gallon water heater.Seems the outer shell was badly dented and unsellable so they removed the burner and regulator leaving just the tank. We used a fish thank recirculating pump to move the water from the smaller cooler tank to the large 40 gallon tank so the thermostat would turn off the cooler when all the water had reached the desired temperature. In our case we plumbed the tanks cool water to the cold water tap and the city cold water into the hot water tap in the darkroom.The drinking fountain tank had a float valve for incoming water which we attached to the city cold water supply so though"Rube Goldberg" it worked well for over 10 years or more. As an aside we also had a Merz rotary tube processor for E6 film which had a chemical storage unit attached.This unit only had an internal heating unit so in the winter months the room temperature was high enough that the cabinet temperature rose above processing temperatures.To solve this we attached an automobile heater core in the recirculating water chiller line and with a small fan fixed to blow through the heater core into the chemical storage unit cooling it enough so the internal heater kept the chemistry at the proper temperature. The water cooler etc. worked year around for us for a long time(and my boss was a happy man).
Necessity is the mother of invention!!!

LabRat
22-Aug-2016, 16:09
Here's what I think I'll try. I will get a small tub for a tempering bath. I'll put a small submersible aquarium pump in it, hook it up to the inlet side of the chiller to push water into the chiller and run the chiller outlet back into the tub.

It would seem to be OK just to connect waterline to chiller and feed directly to water jacket/tempering bath, fill 'em up with cooled water before session, and process... Once you fill a jacket/bath, it will be slow to change temp, so you have a temperature window to work with...

I think that is something you can get the hang of...

Steve K

LabRat
22-Aug-2016, 17:36
Quote from BP; Necessity is the mother of of invention!!!

And what a mother it is!!!!!!!!!!!!!!!!!!! ;-)

Steve K

Harold_4074
22-Aug-2016, 20:05
Kirk,

You mentioned an "after fix tray", suggesting that you are tray processing (as opposed to tanks and hangers). I'm sure you know that tank processing is a bit more forgiving because the thermal masses are much larger and the surface-to-volume ratio is more favorable as well.

I have the same problem that you do, and have been getting around it by putting a few jugs of water in the 'fridge overnight, then adjusting, in a 3-1/2 gallon tank, enough tempered water for presoak, developer mixing, a jacket around a one-liter or one-gallon tank, and a bit more for an intermediate-temperature stop/rinse. Fixer is precooled if it is really warm, but otherwise used at room temperature. On the rare occasions when I need enough that the kitchen fridge gets overcrowded, I turn on a salvaged beverage display (the kind at the ends of supermarket checkout lines). It has a stomper of a cooling system and a pretty vigorous fan because it was intended to pull cases at a time of soft drinks down to about 35F in time for them to be sold. Before acquiring this reefer for kimchi and sauerkraut making, I just used five-gallon kitty litter jugs and crushed ice. The routine let me develop film at a higher rate than I could afford to shoot it...

That said, I have recently gotten pretty heavily into 11x14, which dictates tray processing. The tray-within-a-tray bit works, but takes a lot of water and the average developer temperature tends to vary with the darkroom humidity because of evaporative cooling and the lousy heat transfer characteristics of plastic photo trays. Something that I am working on began with an old polystyrene tray that now contains a serpentine, counterflow, copper-tube heat exchanger, the ends of which come out through bulkhead fittings and end up with hose barbs. I have a small circulating pump, and plan to fill a large, cheap ice chest with tempered water that will circulate through the heat exchanger. In theory, that should allow one fill of the outer tray to last indefinitely if I keep an eye on the ice chest temperature. The developer is always one-shot, so it is made with tempered water and the cooling system just has to keep it within bounds for one development cycle.

In principle, I could just pump water into the outer tray and let it overflow back into the ice chest, but my sink is six inches deep so I would have to give up the spill containment and easy washdown that it provides. Also, the circulating water would inevitably get contaminated with developer, making for a lot of waste and a big cleanup job.

I think you could create my whole setup (except for the beverage cooler, which could easily be replaced by one or more semi-junk household refrigerators) for under $100.

A few experiments with a temperature logger and a couple of thermometers should let me find out just how much cooling capacity is really necessary if I have to move up to a regular water chiller and mixing valve.

One thing that I didn't notice in the earlier posts is mention of the precision of the thermostats in the low-end water chillers---the reading that I have done leads me to expect that they are probably good for plus or minus one or two degrees. This translates, with due regard for Celsius/Fahrenheit conversions, to a range of about 4 F, or the difference between 68 degree and 72 degree chemistry. Probably fine for beer making or saltwater fish, but not what I would want to bet my negatives on. One thing about batch preparation of tempered water is that it is exactly as reliable as your thermometer :)

docw
23-Aug-2016, 09:54
Send the film to Canada its always cold up there.

I wish! I have a similar dilemma right now. Most of the year where I am (Ottawa), you are quite right, and in every season but summer, I have to raise the temperature. I usually just wait for fall to develop film, but I shot a lot this summer and want to get going. However, I calibrated my development for 20C and the groundwater is now 24C.

Luis-F-S
23-Aug-2016, 10:00
I wish! I have a similar dilemma right now. Most of the year where I am (Ottawa), you are quite right, and in every season but summer, I have to raise the temperature. I usually just wait for fall to develop film, but I shot a lot this summer and want to get going. However, I calibrated my development for 20C and the groundwater is now 24C.

So shoot a Zone VII density on film and find the developing time that gives you 1.15 density units over the film base at the higher temperature and you should be good to go!

Kirk Gittings
23-Aug-2016, 10:14
Kirk- what is the ambient room temp in your darkroom? , we leave water in tray overnight to settle to room temp, its usually around 70degree year round, this way the water is always right temp for developing.

About 80-90 with the air conditioner off right now, which I only run as needed. I could run it all the time but don't want the electric cost which are already exorbitant in the summer months.

Kirk Gittings
23-Aug-2016, 10:52
Thanks for sharing your methods Harold.
.
I use BTZS tubes and pull the film to a tray just for the fix stage.

Kirk,

You mentioned an "after fix tray", suggesting that you are tray processing (as opposed to tanks and hangers). I'm sure you know that tank processing is a bit more forgiving because the thermal masses are much larger and the surface-to-volume ratio is more favorable as well.

I have the same problem that you do, and have been getting around it by putting a few jugs of water in the 'fridge overnight, then adjusting, in a 3-1/2 gallon tank, enough tempered water for presoak, developer mixing, a jacket around a one-liter or one-gallon tank, and a bit more for an intermediate-temperature stop/rinse. Fixer is precooled if it is really warm, but otherwise used at room temperature. On the rare occasions when I need enough that the kitchen fridge gets overcrowded, I turn on a salvaged beverage display (the kind at the ends of supermarket checkout lines). It has a stomper of a cooling system and a pretty vigorous fan because it was intended to pull cases at a time of soft drinks down to about 35F in time for them to be sold. Before acquiring this reefer for kimchi and sauerkraut making, I just used five-gallon kitty litter jugs and crushed ice. The routine let me develop film at a higher rate than I could afford to shoot it...

That said, I have recently gotten pretty heavily into 11x14, which dictates tray processing. The tray-within-a-tray bit works, but takes a lot of water and the average developer temperature tends to vary with the darkroom humidity because of evaporative cooling and the lousy heat transfer characteristics of plastic photo trays. Something that I am working on began with an old polystyrene tray that now contains a serpentine, counterflow, copper-tube heat exchanger, the ends of which come out through bulkhead fittings and end up with hose barbs. I have a small circulating pump, and plan to fill a large, cheap ice chest with tempered water that will circulate through the heat exchanger. In theory, that should allow one fill of the outer tray to last indefinitely if I keep an eye on the ice chest temperature. The developer is always one-shot, so it is made with tempered water and the cooling system just has to keep it within bounds for one development cycle.

In principle, I could just pump water into the outer tray and let it overflow back into the ice chest, but my sink is six inches deep so I would have to give up the spill containment and easy washdown that it provides. Also, the circulating water would inevitably get contaminated with developer, making for a lot of waste and a big cleanup job.

I think you could create my whole setup (except for the beverage cooler, which could easily be replaced by one or more semi-junk household refrigerators) for under $100.

A few experiments with a temperature logger and a couple of thermometers should let me find out just how much cooling capacity is really necessary if I have to move up to a regular water chiller and mixing valve.

One thing that I didn't notice in the earlier posts is mention of the precision of the thermostats in the low-end water chillers---the reading that I have done leads me to expect that they are probably good for plus or minus one or two degrees. This translates, with due regard for Celsius/Fahrenheit conversions, to a range of about 4 F, or the difference between 68 degree and 72 degree chemistry. Probably fine for beer making or saltwater fish, but not what I would want to bet my negatives on. One thing about batch preparation of tempered water is that it is exactly as reliable as your thermometer :)

Kirk Gittings
23-Aug-2016, 12:09
It would seem to be OK just to connect waterline to chiller and feed directly to water jacket/tempering bath, fill 'em up with cooled water before session, and process... Once you fill a jacket/bath, it will be slow to change temp, so you have a temperature window to work with...

I think that is something you can get the hang of...

Steve K

True but.........Water is expensive here so I try to conserve it.

LabRat
23-Aug-2016, 15:51
True but.........Water is expensive here so I try to conserve it.

You don't have to leave the water running... Just fill a tempering bath/water jacket before dev operations (does not have to be oversized/too big), have lunch/dinner while solutions come to temp, process, and dump bath in garden... The tempering bath could just be smaller than a picnic cooler or a deep basin container that holds some chem bottles etc... The sink bath can just be some oversized trays... Just an amount of water that cools, and changes temp slowly...

Steve K

ShannonG
24-Aug-2016, 15:49
Sounds simple but what i do is mix my dev. (for my 4X5 dev.tanks ) if the temp is too high i put it in the fridge,for awhile,if its too low i put it in a hot water bath for a bit.unless your dev. times are supper dupper long it will hold its temp close enough..my temp for most developers and films is 68.im in iowa ware the water temp changes a lot.

HMG
25-Aug-2016, 08:38
If I understand, you want to chill water for a water bath for develop, stop, and fix. And you want to maintain proper temp long enough for marathon developing.

My first thought is why not get the water bath (and your water for chemicals) down to the required temp with ice or ice bath and bring the ambient temp in your darkroom down to 70 or 72 deg. So I assume getting and keeping the darkroom temp to 72 or so isn't an option. There are portable air conditioners that might help.

Another (but somewhat McGyverish) solution is to use a small freezer or refrigerator (which you have) to chill water to desired temp. Do do this, you'll need a controller like this (http://www.midwestsupplies.com/johnson-a421-digital-temperature-controller) (there are non-digital versions that should be cheaper). So now you have a 70 deg (for example) environment for your water bath. Now there's 2 options.


Put a 5-10 gal jug of water in early enough to bring to right temp. Use a small pump to move that water to and from your water bath. I'm guessing the volume of water would be large enough to keep the temp close enough to the desired target. The larger volume of water the better. Feed the water bath from the bottom of the jug and return to the top. This would be my choice.
Instead of recirculating pump, use the large jug of water as a "jockey box", running your water through copper tubing in the jug to cool the water down. Again, the larger volume of water the better. And the smaller (diameter) of copper tubing the better.

Luis-F-S
25-Aug-2016, 12:36
Is there a cheapish ($100) water chiller option over the counter that works? Or if not a DIY option that I could build?

Kirk, I think from the above, the short answer is no. I bought a 32 GPH water-cooled Elkay chiller years ago after the emulsion slid off my 8x10 negatives from too hot a wash temperature. It wasn't cheap, but it works and if and when it dies, you can be certain that I'll buy another one! I've moved it with my last 3 darkrooms. You may be able to find a used water fountain chiller that you can adapt for a lower price, just remember that you will need some type of a control valve to maintain temperature. If you use the "cold" tap as the hot side of the control valve, your chilled water supply will go a lot further than if you use the "hot" tap on the hot side of the valve. Good luck. L

jnantz
25-Aug-2016, 13:38
Someone above mentioned a wort chiller, and that's exactly what I would do for the occasional use like this...

Here's a photo of what they look like:

https://www.google.com/search?q=wort+chiller&rlz=1C1ZMDB_enUS561US561&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi95O6h1tXOAhXKkh4KHTHyBiYQ_AUICigD&biw=1731&bih=898#imgrc=LqE-K9X3MKz00M%3A

You can put one in an insulated ice cooler and supply chilled water to your DR all day long with a bag or two of ice.

Depending on the flow, it would be easy to get 50 degree water out of something like this, even much cooler, so you can then set the cold/hot mix exactly where you want it. Keep feeding ice in as the ice melts, and you will have a fairly steady flow.

Since it is for the occasional use, this would probably work better and you can put it in storage easily when not needed.

You can make one by getting 1/4" or 3/8" flexible copper tubing at the home center and coil it to fit whatever you want to put it in, and then put some flared or compression connections on the ends to connect it to your water supply at the sink and then to the Jobo or whatever you are connecting it to.


---Michael

+1

"morebeer" often times has them on sale .. and over $50 i believe is free shipping.

Ivan J. Eberle
16-Sep-2016, 09:07
If you develop in trays and standard tanks, not as easy as with a Jobo... Gravity feed an ice chest to the cold water solenoid hose bib. I scavenged an old fridge to do a heat exchanger thing once upon a time, fridge was free