Ro/Di has foul odor upon startup

[Bolo Tran]

For the last several months, everytime I start up my Ro/Di system for make up water there's a foul odor reminscent of rotten eggs. Is this normal? How do I fix this problem if it's a cause for concern?

[rbnice1]

When was the last tyime you replaced your prefilters and DI?

[jupiter]

I know DI sometimes smells like rotten fish. Is this the smell or is it really rotten eggy?

[Bolo Tran]

I think it really smells like rotten eggs, like passing gas. Goes away after a few minutes though. I replaced the membrane about 8 months ago and just the other day replaced carbon and sediment filter. Di is still ok as it hasn't changed colors yet. Any other thoughts?

[g8gxp]

I also have that. I'm pretty sure that it is the residual wastewater that is left in the system and sitting in the filter canisters. When you turn off the water it doesn't purge all the water in the system so i'm betting there is about 1/4 to 1/2 gallon of water just sitting in the canisters and hoses. typically if i haven't run my unit in more than a week i just let it run for 4-5 minutes before i use the water.

[Bolo Tran]

Thanks for the reply. Can anyone else confirm that this fouls odor is harmless? I've read that it could be a bacterial infection but not sure

[Bolo Tran]

^^^

[tkeracer619]

I have never smelled sulfur from my RO.

IMO it is time for a full filter swap and sterilization of the housings.

I'm sure one of the ro experts will chime in soon.

[sivert55]

i'd pull it apart and dunk it in chlorine and replace the filters.
Then buy an automatic membrane flush timer valve.
Or put in a manual membrane flush kit. They're pretty simple. You should flush the membrane frequently before you start making water. It makes the membrane last longer.

[NadMan01]

i'd pull it apart and dunk it in chlorine and replace the filters.
Then buy an automatic membrane flush timer valve.
Or put in a manual membrane flush kit. They're pretty simple. You should flush the membrane frequently before you start making water. It makes the membrane last longer.

agreed the auto flush works well and keeps your membrane in top condition. As a general practice, if you don't run water out of your ro/di unit daily then you should always scrap the first gallon or two. This ensures that everything is flushed and ready to go.

[tkeracer619]

I used a solenoid from autotopoff.com and two john guest tees on a 7 day programmable timer. I use it to bypass my flow restricter and have it flush the system daily.

[sivert55]

My flush valve switches open for 30 seconds for every 60 minutes of pump time. It's linked to my 8800 pressurizer pump. So as long as the pump is running, the autoflush valve will do its job. Both parts came from filterguys.

[Palancarpets]

I have never smelled sulfur from my RO.

IMO it is time for a full filter swap and sterilization of the housings.

I'm sure one of the ro experts will chime in soon.

X-2 went through the same thing with our unit a while back, but our unit has a pressurized holding tank after the RO unit. I did the sterilization and complete filter change.