3-way diverter valve broke. 2-way instead?

[DaveAZ]

My pool plumbing has (2) 2" suction side lines. One comes from the wall port for the pool cleaner (Kreepy Krauly) and the other comes from the skimmer. These meet into a three way (diverter) valve, which goes into the pump. It was an older model valve which requires lubricaton, and both the handle retaining screw and the grease cup snapped off on their threads.

I need to replace it, but first I'd like to justify it. My biggest problem with it's design is the direction of flow. One of the first things I was taught as a plumbing designer was to NEVER design the direction of flow in a tee fitting to come in at both run sides and go out the branch. I've just searched the internet to see if I could find a friction loss calculation for that scenario and I cannot. http://www.pumpfundamentals.com/pipe_fitting3/pipe_fitting3.html I understand that this is a valve and not a tee, but flow is still is not configured properly from a design standpoint.

The 3-way valve could be replaced by a Jandy 4716 (2" & 2.5" 2-Way NeverLube Valve) on the pool cleaner line and a tee fitting configured with the proper direction of flow. This would eliminate my ability to throttle the skimmer flow, but I never had to do that before aside from once while trying to calculate head.

Would this design change make any difference to my friction loss, or am I overthinking this?

 

[PoolGuyNJ]

The grease cup and guts can be swapped without replacing the body, thereby avoiding any plumbing change.

House plumbing and pool plumbing are similar but different. Your current configuration is normal.

If only one in and one out are open, treat it like a 90 or straight pipe, depending on the configuration.

Scott

 

[DaveAZ]

The grease cup and the handle retaining screw together cost almost the same as the newer greaseless valve. The existing valve has been exposed to the AZ heat and sun for 15 years.

It is almost the same amount of hassle to take the existing valve apart to remove the broken threaded plastic pieces as it is to do the plumbing- Wouldn't I be better off updating the part?

I believe the poor design regarding the path of flow is actually a compromise for making it idiot-proof. The user isn't able to accidentally shut off all of the suction plumbing, but they can regulate the ratio of flow between the two pipes completely.

 

[PoolGuyNJ]

The thread stem is easy to remove. Drill a small hole in it's center and tap a small flat head screwdriver in. Turn and out it comes.

Lifting the handle so the tab below doesn't hit the stop when turning allows you to block the common port.

To remove the old grease cup fitting, again, tap the small flat head in it's center and turn.

Changing the plumbing is usually more of a PITA.

Scott