Soda machine chiller?

[KEITHMC]

Ok guys I have a soda machine right next to my sump it has a refrigeration unit on top and maintains a 15# of ice on the coils in a water bath!

Ice on the coils

I am planning on using the water bath to circulate through a heat exchanger in the sump with a pump on a dual stage temp controller!

Front of the unit

I will be using the existing drain, which I have fitted with a 3/8 drain line

What I need now is some suggestions for the heat exchanger and the pump!!

 

[xrunner1234]

What's the BTU rating?

 

[KEITHMC]

not sure the only info plate on the thing only gives 8.5 amps uses 134a and has a capicity of 6.5oz of refirerant

 

[jay24k]

Is that a brass/copper fitting on the end? I read a few people on here having major issues with using those type of fittings.

 

[landragon]

I would not use that if it were brass.

 

[KEITHMC]

will not matter the loop will be filled with the fresh water from the ice bath the only part that will be exposed to saltwater is the coil in the sump and the tubing just need to know what other people have used for heat-exchangers in their sumps!

 

[orlenz]

McmasterCarr.com sells titanium tubing, you can roll some aorund a jig and make a coil and run your tank water through it.
make sure you get the anealed (soft) tubing.
1/2" is $109 for a 3 foot length.

 

[KEITHMC]

just spoke with aqua logic and their drop in coil is around $130 just for the raw coil any other sugesstions for a good heat exchanger?

 

[xrunner1234]

You could probably get away with using 1/4". Did you price that?

 

[KEITHMC]

no the price i got was for a 3/8 in coil the same as the drain line on the ice bath i think i am going to use a mag 2 for circulation and a rk2 for the temp control i think 1/4" would have too much head loss for the mag 2!

 

[KEITHMC]

Well I purchased 30ft of 1/2 in poly tubing hooked it to my 200gph pump and placed the coiled tube in my 30gal mix container and plugged it in it pulled down 10f in 1 hr but I think I am going to go with a titanium tube heat exchanger for better transfer and the fact that I just donââ"šÂ¬Ã¢"žÂ¢t want to put 25ft of coiled tube in my sump!

I am going to get a reefkeeper2 to control my circulating pump anyone had any problems with these?

 

[douggiestyle]

might try stainless steel. from all that ive read ss will corode in salt water. but at a fairly slow rate if in constant submersion. not a chance i would take with the ss under a fair ammount of internal pressure and circulating some type of refrigerant other than pure water. but if you circulated only pure water, if a leak occured who cares. just replace the tubing. might try a ss coil (try a flex gas connector) in the cooler area. also one in the tank sump. connect them with poly and a pump to circulate.

 

[KEITHMC]

it is pure water circulating at about 30-40f

 

[douggiestyle]

see you are ok with ss then. if the line was to break there would be no contamination.

ti is hard to bend from what ive read. the correct technique is to fill the ti with cerro bend. seal the ends and then use a bender used for thin walled ss tubing. i think it was called a 3 axis or roller bender. then remove the cerro bend. use acid to remove cerro bend residues from inside the ti. then anneal if using in high pressure or stress area.

with a ss flex gas connector the ss is of the very good variety that resists corrosion (303 ?) i have a table some where. also no special bending required. no special order, buy one at hd. get a long one, maybe 6'.carefully drill out the flares to remove the brass fittings and use an all nylon compression fitting in its place.

 

[KEITHMC]

Cool think its time to go back to HD and shop again =)

 

[douggiestyle]

make sure and clean the ss real good. also might try cracking the brass fittings off then cut off the flare.

good luck.
post the results.

 

[douggiestyle]

oh, and do not get the kind of flex connector that is painted. even though it says it resists corrosion longer. the last thing you want is paint flakes floating around

 

[Avast Marine]

Here is something that I have been thinking about. Cold plate.
All SS, takes minimal space is rectagular and sub $100:rollface: .

 

[kgross]

Don't go with SS, there are only a couple of types of stainless that will not carrod in saltwater, go with titanium. If SS would work the chiller manufactures would not be using titanium since SS is less expensive.

Also on those coldplates they are SS tubing in aluminum. Unless you want lots of aluminum in your tank I would not suggest them.

Either spend the money on the titanium heat exchanger or use the poly tubing

Kim

 

[fitti69]

If you really want to go with stainless tubing make sure it is high grade and non ferrous { a magnet wont stick } . If it is not , you will just be wasting money and kicking yourself later . Lower grade AKA magnetic stainless has to much iron in it , atleast i wouldnt want it in my tank . This is why the aquarium chiller industry uses titanium for most of there applications . High grade stainless is strong as hell , and stands up to corrosion . Only problem is it has a low tensil strength , splits and tears easy when you try to form it . Titanium on the other hand , its soft and malible . Also has better corosion resistance . That "titanium" color is a layer of corosion that helps protect the metal . So i guess what i am saying is , if you can find the SS tubing on the shelf it probally wont work for you . The only reall way to bend the stuff in tube form is through hydroforming .