Adding a DI chamber to an existing household RO unit?
 

I am helping a friend add a DI chamber to their household RO unit. However, the unit is in the basement and I would like to hook up the DI on the main floor under the kitchen sink. This way I can easily "T" off the line where it comes up for drinking water, and hook up a reservoir on the main floor (where the tank is).

Does the DI chamber need a specific amount of pressure going through it? I'm thinking I'm going to lose a lot from the basement to the main floor. As far as I can tell my unit just trickles through the DI chamber so I'm hoping this will work.

I would think you need a storage tank, one with the rubber bladder in it. It would give you the pressure you need plus, when you ask for drinking water upstairs, you will get a glass, not a trickle.
I installed a tank for my friend in his basement and it worked fine.
Not endorsing these guys, but here is a pic of the type of tank I mean.

http://watergeneral.com/product10.aspx

Thanks for the input. There is a storage tank similar to the one you mentioned installed downstairs. I hooked up the DI chamber upstairs where it is convenient to have a top up/water change reservoir. However, now the DI chamber is plumbed in after the drinking water storage tank. I guess my question about pressure comes back into play. Now I am worried there is too much pressure going through the DI chamber because of the pressured storage tank.

Should I just have them drain the tank before running the DI chamber? It is only a few gallons tops.

Thanks

Not to worry. The pressure after the storage tank is equal to the pressure without the tank. Whether you have a tank or not, the end pressure is the same.
All the DI chambers I have set up are after the tank.
After the tank I put in a tee, one goes to faucet and fridge, the other to the DI