CDL wash tank heater?

[Squaredeal]

Does anyone have a good solution for adding a heater to the wash tank on a CDL RO?

[ennismaple]

Good question - great minds think alike! This is on my off-season to-do list for 2014.

We have a "spare" 3000W hot water heater element that I planned to put in the threaded hole in the back of the wash tank on our CDL RO. Our wash tank has two threaded holes - a smaller one and a larger one and the larger one will take the hot water element. I was thinking about putting it on a timer so I can't forget to turn it off.

Anyone done this?

[Squaredeal]

Mine does not have any spare holes. If it did I would use one like this: http://www.mcmaster.com/#immersion-heaters/=m5eoqd I think the two holes in yours are for the element and temperature control that are shown in the CDL catalog.
I think I'm going to have to punch a hole and weld a npt fitting on to make this work. 5 C permeate is just too cold.
I do like the idea of a timer...

[tstew]

Was wondering why not just put a temperature shut off instead of a timer. If you look around you can find them cheap enough or used off an old hot water tank.

[wiam]

I use a 14 gallon plastic barrel for a wash tank. I put a 3500 watt element in a 1" bulkhead fitting. The elements have a straight thread but seals fine with the gasket that comes with it. I am still working on temp control. Regular water heater thermostats are kind of variable. I used one on a chicken scaulder and there could be 15 degrees difference. I am thinking about some of the controls some have used for draw-offs.

[802maple]

I have installed plenty of heaters on the CDL machines that don't have the extra hole. All you have to do is on the outlet of the tank is install a "Tee" where it comes out with the 2 holes that lineup going into the tank and use the 90 degree side for your pump feed. Then you can thread in the element. I would use a float switch so that when you drain the tank it won't come on and it will shut off when emptying. At the same time it, you should have it controlled thermostatically so it doesn't heat up to much before rinsing or washing.

[Squaredeal]

An excellent and practical solution. Thank you.

[Jeff E]

Sorry for my ignorance.
Why heat the water in your wash tank? Quicker wash cycle? Dosn't the time circulating the wash solution aid in cleaning as well as the elevated temp.?

Inquiring minds want to know!

[ennismaple]

I've been told that the membrane only "opens up" above 35 Celcius so you ideally want to start at that and allow it to re-circulate until it hits 42 C. If you need to take cold permeate from 5 C to 35C that can take many hours and doesn't benefit the membrane cleaning much. Ideally, I want the RO to turn off on high temp before I leave the sugar camp so i can put the machine on rinse cycle overnight.

[Profirefighter]

A real simple solution for me was to put 50 feet of stainless coil in my steam pipe above the preheater. Divert some of the water off the RO through the coil into a holding tank and mix with cold water to bring the temperature to around 38 C. The water from the coil is coming out close to boiling so it doesn't take very long to make a lot of warm water for washing the RO. Requires no extra power or energy. I spent around $70 and found it on ebay from New York brewing Co.

[Squaredeal]

Here's a picture of my installation...
7749
It's so cold here that my permeate is often just barely above freezing. It takes forever to get up to temperature where the soap will work (about 77). I too like to let it finish washing before leaving for the night, and now I can.
Also, this set up enables the "hot flush".