A new way to beat the heat

[Cabinetman]

Well with the summer heat my tank temps have been rising and it was time to act. Having a swimming pool I’ve seen people with big coils of hose exposed to the sun and circulated to heat their pools so this got me thinking. I’m on a well and my water is ice cold coming out of the tap so I thought I wonder if I cou use the same principle to cool my tank. So I bought a Neptune 1/4 water control solenoid switch and 150’ of 1/4 clear Rodi line and set it up so the coil in submerged in my sump and I programmed my apex so the the valve operated Like a chiller. Open when temp hits 26.7 and closed when temp lowers to 26.6. Well when I first got it running my tanks temp was 27.2 and it was incredible how fast my temp dropped... in an about 600 gallon system or more. My next step is to plumb it so that the water exiting my sump actually feeds my Rodi instead of just waisting all the water. The other thing.. the water coming out of the sump coil is still fairly cool so I’m going to add a few hundred more feet of line to extract as much of the cold as I can. But already I can see a huge difference in the water temp after it goes thru the coil. So ...killing 2 birds with one stone so to say!!! Here’s a pic of my apex graft. You can sure tell when the water is flowing the way the temp drops from the previous day. It drops like a rock! The second graft was from this morning It’s easy to tell when I shut the flow of cold water off that’s for sure. Today’s graft will be very interesting to see

 

[Reeferdood]

So every time the solenoid kicks on the water goes thru the coils and begins to make RO/DI water?
Interesting concept!

 

[Cabinetman]

So every time the solenoid kicks on the water goes thru the coils and begins to make RO/DI water?
Interesting concept!

That’s exactly how it works. I have my Rodi set up on a time to come on for 4 hours a day every afternoon anyway so I shouldn’t really end up using much more water than usual. Just so you guys know too. My temp probe is in my display so the drop is not just in my sump.

 

[Reeferdood]

Pretty cool..

 

[Cabinetman]

It’s working better that expected! It’s been 2 hours since all my lights came on. It’s was set to start chilling at 26.6. The climb was straight up fast until it came on now it’s flat without any more rise. Here’s a pic of the graft.

 

[Muttley000]

Great idea on feeding the Rodi, now you just need to automate it to flush itself on startup to save your DI resin

 

[Cabinetman]

Another update. So just so you guys know it’s a heat wave here today. 30c which is the hottest day of the summer by 5c. And I’ll let the chart speak for itself. I have a vertex Rodi so it flushes every time anyway and besides. I don’t worry about di resin anyway. I get 4 tds which is way better than just using tap water. Which I used for quite a while with no troubles.

 

[Cabinetman]

I’m going to say this was a success.

 

[Cabinetman]

So it’s been a few days and I couldn’t be happier. My tank has stayed between 26.6 and 26.3. I’m sure with the heat wave we are experiencing and no ac my tank would have hit 29 or higher without the coil. This is a very efficient way to cool a tank if you are on a well and have lots of water. With a larger coil I think it will be close to 100% efficient meaning the water that gets circulated will be the same temp as tank exiting the coil. Once I get my $60 500ft roll in I’ll post an update as I plan on testing the temps going in and out. Here’s my last graft as you can see it leveled right out.

 

[dhof]

I recently accomplished a similar thing by pointing a fan at my media reactor. If your coil idea needs a little help, just point a fan a the coils.

 

[Cabinetman]

I recently accomplished a similar thing by pointing a fan at my media reactor. If your coil idea needs a little help, just point a fan a the coils.

How big is your tank? Remember I’m cooling 600 gallons lol

 

[dhof]

How big is your tank? Remember I’m cooling 600 gallons lol

Ahhh, I skimmed too quickly and missed the size of your tank (mine is 12 gallons!). Now that I actually *read* your post, it's a pretty brilliant solution you have going on there.

I have one of those solar heaters outside of my pool where water is pumped through a few hundred little black tubes. It definitely adds heat from the sun during the day, but I have to make sure to turn the pump off or divert the flow at night. It's crazy how fast the pool temp can drop by running flow through the little tubes overnight, which is just heat loss through air I think. I guess I was thinking for those without ice cold tap water (and probably way smaller tanks) it might be feasible to just create some coils with RODI tubing, pump tank water through the coils, and point a fan at the coils. I wonder if the heat loss of the coils/fan would be greater, or even equivalent, than the heat loss of the cold water. My guess is that fan/coil would be way less efficient than coldwater/coil except that the fan would not be limited by the size of your RODI container