RO/DI question

Well in order to product RO/DI water, the water must first go through the RO membrane then through the DI element. I would imagine there would be more resistance when making RO/DI water in comparison to just making RO water.

When making RO water, typically the water comes out of the membrane then through a carbon filter. I don't know if the carbon element has more resistance than a DI element.

That may be the reason ... if you are getting higher flow out of RO.
 
How is your system plumbed? The flow should be the same if the DI follows the RO unless you have a pressure tank that stores RO water and then passes pressurized RO water through the DI resin.
I hope you don't have a carbon filter after the RO unless you are using it for drinking water only, they put TDS back into the water and are a bad idea except for drinking water tastes and odors.
 
AZ,
I have a similar issue and I think it's good to get this feedback. I have a pressurized tank that stores the RO water before sending it either to the faucet or to the DI resin. I always turn the tank ballvalve off before getting DI water so that it flows slowly as opposed to a jetstream from the tank. The idea is to maximize the dwell time of the RO water in the DI resin. Is this necessary?
FB
 
If your DI cartridge is packed tightly and is a large one like in the standard 10" vertical canisters, flow through a 1/4" tube should have sufficient residence time in the resin bed. I have talked to Spectrapure and they tell me they have tested their MaxCapdual DI system in standard 10" size at up to 20 GPM with good results. I run my MaxCap from a14 gallon pressure tank and have no problems at all maintaining a TDS of less than 0, or about 18 megaohms.
The key is really packing the resin tightly so it cannot possible short circuit or channel.
 
Back
Top