Flow restrictor in backwards?

firebirdude · 12/24/2014, 06:45 PM

So I have the 90gpd Spectrapure RODI with a two-stage add-on. Usually around ~78psi. I accidently cut the tail short on my flow restrictor while installing a flush bypass. Didn't even realize it until I noticed very poor output. Like 11:1. I had some credit at BRS, so I bought their 75gpd and their 100gpd flow restrictor (sorry Buckeye, next time)...knowing that those are just advertisment numbers and I need to use whichever one gets me to the waste : output ratio I want. I threw in the 75gpd restrictor and still got terrible output (11:1). I threw the 100gpd restrictor inline and got better output (7:1). Then I decided to flip the restrictor around, backwards to the flow arrow printed on it. First thing I noticed is that it makes a bit of noise as water is forced through it. Second, I notice my pressure is now up to ~85psi. I'm now getting about 4.5:1 waste : output. Should be no harm no foul, yes? And why is this fighting me so? It's an advertising 90gpd membrane and I'm having a hellava time dialing it in now...

firebirdude · 12/25/2014, 09:33 PM

Anybody?

Buckeye Hydro · 12/27/2014, 07:18 AM

1. Install the restrictor pointed in the correct direction
2. Use (or trim) the restrictor to get something close to a 4:1
If you want LESS waste water, go for a tighter restrictor (e.g., a 50 gpd restrictor is tighter than a 75 gpd restrictor). If you shorten an existing restrictor you will allow MORE waste water.

It's really no more complicated than that.

Russ

firebirdude · 12/27/2014, 08:17 AM

These are inline restrictors. Cannot be trimmed. And installing this one backwards is the only way I could achieve even close to 4:1.

Buckeye Hydro · 12/27/2014, 08:24 AM

In that case, look at the three or four digit numbers stamped on the side of the restrictor. The lower the number, the tighter the restrictor.

Or just get rid of that type and use the capillary type.

Russ

firebirdude · 12/27/2014, 08:36 AM

UNderstood. Just asking if have it in backwards really causes any problems, other than increasing restriction....which it seems I want in this case. Just trying to make use of what I have versus buying more.

Buckeye Hydro · 12/27/2014, 10:25 AM

Depends upon what sort of restrictor is inside your cartridge. You'd have to break it open to find out.

12/24/2014, 06:45 PM	#1
firebirdude User and Abuser Join Date: Aug 2008 Location: Oklahoma Posts: 1,836	Flow restrictor in backwards? So I have the 90gpd Spectrapure RODI with a two-stage add-on. Usually around ~78psi. I accidently cut the tail short on my flow restrictor while installing a flush bypass. Didn't even realize it until I noticed very poor output. Like 11:1. I had some credit at BRS, so I bought their 75gpd and their 100gpd flow restrictor (sorry Buckeye, next time)...knowing that those are just advertisment numbers and I need to use whichever one gets me to the waste : output ratio I want. I threw in the 75gpd restrictor and still got terrible output (11:1). I threw the 100gpd restrictor inline and got better output (7:1). Then I decided to flip the restrictor around, backwards to the flow arrow printed on it. First thing I noticed is that it makes a bit of noise as water is forced through it. Second, I notice my pressure is now up to ~85psi. I'm now getting about 4.5:1 waste : output. Should be no harm no foul, yes? And why is this fighting me so? It's an advertising 90gpd membrane and I'm having a hellava time dialing it in now...

12/25/2014, 09:33 PM	#2
firebirdude User and Abuser Join Date: Aug 2008 Location: Oklahoma Posts: 1,836	Anybody?

12/27/2014, 07:18 AM	#3
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	1. Install the restrictor pointed in the correct direction 2. Use (or trim) the restrictor to get something close to a 4:1 If you want LESS waste water, go for a tighter restrictor (e.g., a 50 gpd restrictor is tighter than a 75 gpd restrictor). If you shorten an existing restrictor you will allow MORE waste water. It's really no more complicated than that. Russ

12/27/2014, 08:17 AM	#4
firebirdude User and Abuser Join Date: Aug 2008 Location: Oklahoma Posts: 1,836	These are inline restrictors. Cannot be trimmed. And installing this one backwards is the only way I could achieve even close to 4:1.

12/27/2014, 08:24 AM	#5
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	In that case, look at the three or four digit numbers stamped on the side of the restrictor. The lower the number, the tighter the restrictor. Or just get rid of that type and use the capillary type. Russ

12/27/2014, 08:36 AM	#6
firebirdude User and Abuser Join Date: Aug 2008 Location: Oklahoma Posts: 1,836	UNderstood. Just asking if have it in backwards really causes any problems, other than increasing restriction....which it seems I want in this case. Just trying to make use of what I have versus buying more.

12/27/2014, 10:25 AM	#7
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Depends upon what sort of restrictor is inside your cartridge. You'd have to break it open to find out.