I need to replace the plastic knob to this Delta tub/shower valve.





Apparently there are many that look similar with different model numbers: H71, RP17451. RP2389, RP2391 and more. Is there a way to tell exactly which model I need?

H71 fits different cartridge.

RP2389 is for lav faucet.

RP2391 is for 600 series shower valve and I believe that is what you have.

Rp17451 is also for 600 series shower valve. I don't know the difference between it and RP2391.

I've always used RP2391.

Thanks Curly I will get the RP2391.

For some reason this knob is getting very wobbly/loose. I tightened the screw under the plastic cap and didn't help. May be the diamond shaped recess is worn, not sure.

RP 17451

I have two such showers in my home.

The 'knob' may have cracked with age.

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

curly,

re: RP2391 different trim cap design


same knob



the one i referenced has a 'wave' pattern and is 'pretty'

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Good Eye Bern!

Thanks for the info.

curly,

i have 2 600 series in my own home


simple

dependable

EASILY rebuildable



i don't need no modern tech to adjust water temp




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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Bern,

Inquiring minds what to know if the shower valves were installed by a licensed, insured and bonded plumber ?

Just kidding.

Those Delta 600 series shower valves work well and are easy to repair that is for sure.

Yes, they were.

All permits checked and verified before purchase.

House built in 1991, purchased by myself 2004.

Type "L" Cu throughout.

PVC DWV properly pitched and 'hung' in crawlspace.


................. now the ELECTRICAL and HVAC is a different issue, but finally totally corrected 2020

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Curly, I find these valves not "easy to repair". I have not been able to remove the "retainer dome" over the ball. I have tried a channel lock, a strap wrench, I have tried to heat it up, tap on it all around lightly, I have tried different kinds of lubricants, none worked. I have three of these in three rental apartments, and each time someone moved out I tried to open it up to replace the ball and so far no luck. The thing is they are working and do not need replacement YET, but I want to open it just to know that I can reopen if needed in case of emergency. I do not dare giving it too much torque because I read that this can result in the soft copper tubings behind being torn apart.



Edited 1 times.

One question I have is when I turn the handle to the left for hot and right for cold, if I tilt the handle down while it's in the left or right position the water doesn't shut off 100%, there is some dripping. The only way to shut it off 100% is to turn the handle to the middle and down. Is it supposed to be this way or this is a problem with the ball and springs inside?

problem with the springs, seals/washers, and or the ball

that is EXACTLY when they should be replaced

BEFORE it fails to shut at all



tool i use:



then 'never-seez' on the threads

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

If you can not unscrew the cap with tool as Bern suggested. I will use a Dremel with abrasive cut off wheel to cut a slice in cap (Delta RP50) and a flat blade screw driver to pop it open.

Have to have a delicate touch and not slice too deep into faucet body/threads. Slow and steady.

Lube the threads before installing new cap.

when replacing the cap it is NOT, repeat NOT, necessary to tighten more than a 'smidge' beyond finger tight

the valves from the factory are easy to service

the ones 'worked on' by 'handypersons' not so much


the top 'cross notched' insert is what secures the ball and seats

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

dome nut in stainless..

[www.deltafaucet.com]

Here is pretty good video showing how to cut off nut etc for a Delta 600 series shower valve....

[www.youtube.com]

He uses a hacksaw....I use a Dremel and usually don't cut into chrome sleeve like he did.

He did not lubricate threads before he installed new rp50...he should have.

If I had to guess he may have overtighten the rp50 also....but I was not there

I have a Dremel so will keep that in mind next time I need to open the dome retainer. I need to buy a spare dome retainer to stand by just in case! Thanks!