RO/DI with two chloramine filters: Replace one or both?

[james670]

I just got an AquaFX 5-stage RO/DI unit with 2 "Chloramine Blaster" filters. The AquaFX documention mentions that the two filters in series will yield approximately 8000 gallons of water. Everything I've read says that we need two in series to maximise contact time with the carbon because chloramines are so hard to treat, but when it comes time to replace the filters (either after 8000 gallons of DI + wastewater or if I test the post-chloramine water and get >0ppm of chlorine), does the second one still have life in it?

Can I swap the first for the second and place a fresh chloramine filter in the second carbon chamber? Or do I have to swap out both? Or alternatively, if I want to do a swap of the first for the second, should I do it at an earlier time, say, at 6000 gallons of water?

Just trying to find a way of getting the most out of my chloramine filters and making sure I only toss out carbon that's fully spent.

 

[Malcontent]

I have 5 carbon stages in series and test after the 4th. If there's detectable chlorine I retire the first stage, move the rest up one position, and install a new one in the 5th position.

 

[AJsReef]

I replace both of my carbon filters at the same time. I do save one of them for after my pressure tank for drinking purposes.

I have a Hana to check for chlorine but change out every 3 months way before capacity just to stay safe

 

[james670]

My two choramine chambers are connected via bolts, so I can't test after the first chloramine chamber. The AquaFX setup has a tee and valve that hangs off the second chamber to flush out new filters, so it's even easier for me to test after the second chloramine filter than simply testing waste water.

Sounds like with just two chloramine filters, I have to treat the two in series as a single filter and just change out the whole thing when I get >0 chlorine after the second filter. It would have been nice to know how depleted the second filter is when I get to this stage, but I guess it's better safe than sorry. Thanks for your responses!

 

[Opus]

My two choramine chambers are connected via bolts, so I can't test after the first chloramine chamber. The AquaFX setup has a tee and valve that hangs off the second chamber to flush out new filters, so it's even easier for me to test after the second chloramine filter than simply testing waste water.

Sounds like with just two chloramine filters, I have to treat the two in series as a single filter and just change out the whole thing when I get >0 chlorine after the second filter. It would have been nice to know how depleted the second filter is when I get to this stage, but I guess it's better safe than sorry. Thanks for your responses!

They are using regular housing so you could easily replace the fittings on the 2 chambers and add a tee to it. I've changed mine over the years to suit my purposes. If you do it by testing the water after the second chamber then you will have to change both carbon filters since both will be used up by the time the second one lets chloramines thru. Also, special carbon blocks are not needed to break down chloramines. Any good quality carbon block will break them down. The special carbon blocks are just more efficient at doing it but from a cost perspective I'm not sure if they are better in the long run due to their higher cost.

 

[james670]

They are using regular housing so you could easily replace the fittings on the 2 chambers and add a tee to it. I've changed mine over the years to suit my purposes. If you do it by testing the water after the second chamber then you will have to change both carbon filters since both will be used up by the time the second one lets chloramines thru. Also, special carbon blocks are not needed to break down chloramines. Any good quality carbon block will break them down. The special carbon blocks are just more efficient at doing it but from a cost perspective I'm not sure if they are better in the long run due to their higher cost.

Makes sense, thanks. If I was willing to make minor adjustments to my RO/DI unit before, I shouldn't be afraid to split the chambers apart to add a tee line. But maybe after I've used the unit for a couple of thousand gallons first before start playing around with it. I certainly hope the chlorine levels won't leak through earlier than that!

 

[PatW]

I use my sediment filter to cue me for changes. When the sediment filter gets kinda pale brown, I change the sediment filter and my 2 carbon filters. It seems to work out OK. The water here is just chlorine and not chloramInes.

 

[Krowmannsreef]

with any redundant filter you replace the first in the the loop with second and replace the scound with anew one. the first is discarded and the second is pre primed for the new one.