D1203 vs D1225 style upper baskets?

[Hatsuwr]

What are the advantages of the D1225 style?

Upper Screen/Diffusers with Twist-n-Lock Connection - SWT

SWT's Upper Screen/Diffusers with Twist-n-Lock Connection (P/N LC-D1203-01, LC-D1203, LC-D1203-02).

www.swtwater.com

Stacked Upper Screen/Diffusers with Twist-n-Lock Connection - SWT

SWT's Stacked Upper Screen/Diffusers with Twist-n-Lock Connection (P/N LC-D1225-03, LC-D1225-06).

www.swtwater.com

By my count, my D1203 styles have around 45 slots of 2.25" length. Judging from the photo, the D1225 has 11 interrupted slots around a circle with ~1.2" radius. That gives total lengths of 101.25" for the D1203 and <83" for the D1225 (probably closer to 70").

 

[ditttohead]

In general the "Heavy" screen is used for upflow applications. The light duty screen is used for downflow applications. If you are going downflow there is no need for the heavy screen as the screen is rally only used as a diffuser so as to "diffuse" water flow and lessen the potential for channeling. Here is a great picture of a 9100 with a flow rate at 20 GPM, notice the tank that is online (right side) has the resin pushed to the side. One of my customers called and asked why this was happenning, I told him it was missing the top screen. He removed the valve and confirmed the screen (diffuser) was missing. Upon installation of the screen the media was running level. If you look at commercial equipment, we rarely use screens, instead we use simple diffusers, see picture below.