Kohler Rite-Temp Shower Valve: Find Your Valve and Replace the Cartridge
Rite-Temp is Kohler's name for its pressure balancing shower valves. Kohler's spec sheet for the K-304 valve says Rite-Temp pressure-balancing technology maintains water temperature within plus or minus 3 degrees F. When the shower starts to drip after you shut it off, or runs hot and cold while someone flushes a toilet, the parts to look at sit right behind the handle: a black mixer cap and the pressure balancing unit (PBU) under it.
The catch is that Kohler made several single-handle valves that look alike from the front, and they do not all take the same parts. This guide follows Kohler's own way of telling them apart, then walks through the cap and PBU swap in the order Kohler's service instructions give. If you want to know what the PBU is doing in there, our sister site explains how a pressure-balance shower valve works.
Kohler's service page opens with this: before doing any repairs to your Kohler valve, shut off your water. Kohler says many Rite-Temp valves have built-in screwdriver stops, but its spec sheets list the K-304-K without them and the K-11748-K less them, so you may need to close the main shut-off for the house. Kohler's install guide also warns not to force the handle in any direction, because forcing it will damage the valve. Our advice: if a part will not come out, stop and call a plumber. Kohler's install guide gives its Customer Care Center number, 1-800-4KOHLER, for anyone who does not understand its instructions.
Step 1: find out which Kohler valve you have
Take the handle and the round trim plate (the escutcheon) off first. Kohler's guide to identifying single-control shower valves starts from there. If there is an adaptor on the end of the valve stem, Kohler says to remove its screw if it has one and slide the adaptor off. Then it asks one question: is the valve stem square or round? Then it asks what the cap is made of, and on a round stem with a black plastic cap, how many screws hold the cap to the valve body.
| With the trim off you see | Kohler says your valve is | The parts it takes |
|---|---|---|
| Round brass stem, black plastic cap, 2 screws, no diverter button | K-304 Rite-Temp | Mixer cap and PBU (Kohler GP77759 cap, GP500520 PBU, or the GP76851 kit) |
| The same, with a diverter button | K-305 or K-11748 Rite-Temp with diverter | The same mixer cap and PBU, per Kohler's identifier |
| Round stem, black plastic cap, 4 screws | K-8304 Rite-Temp | A one-piece cartridge. Not covered here. |
| Round stem, black plastic cap, 6 screws | K-306 or K-2971 Hi-Flow Rite-Temp | Not covered here. |
| Round stem, brass cap | Early K-304 pressure balancing valve | Kohler lists a PBU and a plunger kit. Not covered here. |
| Square brass stem | K-15700 or K-15701 Coralais | Mixer cap GP77886. Kohler also lists a PBU. |
| Square black or gray stem | K-15877 Coralais | Not covered here. |
| Square silver stem | K-15153 or K-15155 Coralais | Not covered here. |
Kohler's K-304 service page names the GP77759 cap, the GP500520 PBU and the GP76851 kit. Kohler notes that the K-305 was discontinued in June 2010 and replaced by the K-11748. If your valve is not in the table, Kohler's identifier ends with its Customer Care number.
Step 2: the cap and PBU together, or the PBU alone?
Kohler's identifier gives a clear rule for its Rite-Temp valves with a diverter. If you are fixing a leak, replace the mixer cap and the pressure balancing unit. If the water temperature swings, replace the pressure balancing unit. Kohler's dripping guide says the same about leaks: if a drip or leak continues, the issue could be an internal seal or tear, so replace the mixer cap and PBU kit.
Step 3: replace the mixer cap and PBU
These steps follow Kohler's Rite-Temp K-304 service part installation page and the Kohler service kit sheet that Ferguson links for the GP876851 kit. Our own tip, not Kohler's: lay a towel in the tub so a screw cannot go down the drain.
Step 1: Shut off the water
Close the screwdriver stops if your valve has them, or the main shut-off for the house. Kohler says to shut off your water before any repair.
Step 2: Take off the handle and trim, and note the cap
Pull the handle and the escutcheon. Before anything else comes off, note the position of the tab or the word UP on the cap, as Kohler's kit sheet says. Kohler's temperature page describes a black O-ring, a caution tag and a red collar on the round brass stem (older models have a black collar). The collar sets the hot limit, which you check again once the new parts are in.
Step 3: Remove the screws, the collar and the cap
Kohler's service page lists it in this order: remove the two screws, remove the collar (it may not be present), then remove the cap assembly. If your new cap comes with a metal collar, Kohler says to use it.
Step 4: Pull the PBU
Kohler says to remove the pressure balancing unit using pliers, and its kit sheet says the same: use pliers to pull it from the valve body.
Step 5: Clean the valve body
If there is debris or brass burrs inside, Kohler says to clean it out with a 50/50 white vinegar and water solution, and to use a Scotch-Brite pad on burrs, taking care not to scratch the sealing surface.
Step 6: Grease the O-rings
Kohler's kit sheet puts two new O-rings on the back of the new PBU. Kohler says to apply silicone lubricant to the small O-rings on the back of the PBU and to the larger O-ring around the cap assembly. Its kit sheet also says to lubricate the new O-rings on the back of the cap. Use silicone only: Kohler says petroleum-based lubricants harm the O-rings, seals and plastic parts.
Step 7: Set the new PBU in straight
Line up the tab inside the brass body with the notch on the back of the PBU, as Kohler's service page says. Kohler's kit sheet adds: align COLD on the unit with the cold inlet and fully insert it. Then the warning that matters most: do not place the PBU in the brass body at an angle and rotate it. Kohler says that moves the small O-rings out of position and will cause the valve to leak. The PBU should sit completely level in the valve body.
Step 8: Fit the cap, then the collar and screws
Place the black cap on top of the PBU and press it into the brass body with the black top at the 12 o'clock position, as Kohler's service page says. Kohler's install guide puts the tab up, or down on a valve installed reversed, back to back with another, which is why the position you noted in step 2 matters. Then put the metal collar over the cap and tighten the screws on the left and right. Kohler is firm on the order: do not install the metal collar before the black cap. If the collar ends up between the PBU and the cap, the cap will not seal.
Step 9: Water on, test, then the trim
Kohler's kit sheet says to turn on the water supply and check for leaks, fit the handle on the stem to check that it works, and then reinstall the trim. Our advice: set the hot limit (next section) before the trim goes back on.
Kohler says the K-304 Rite-Temp valve can be adjusted for your maximum hot water temperature, and its install guide says the maximum setting must be set before installation is complete. With a new cap, our advice is to do this before the trim goes back on. With the black O-ring, the caution tag and the red or black collar off the stem, rotate the stem clockwise to turn the water on and test the temperature with a thermometer. When it reads the temperature you want, put the collar back on the stem, then turn the stem counterclockwise to turn the water off. Kohler says the water temperature should never be set above 120 degrees F, and warns of the risk of scalding: high water temperature can cause severe burns. A pressure balancing valve does not make up for changes in the supply temperature, so Kohler says to check the setting again after seasonal changes and after water heater service.
If it still drips or swings
- A short drip is normal. Kohler says showerheads can drip for up to 90 seconds after the valve is turned off.
- A leak right after a new kit points at the O-rings or the collar. Kohler says the kit's O-rings must be in perfect condition and installed exactly as instructed, and that the metal collar must sit in front of the mixer cap, not between the cap and the PBU. Our advice: shut the water off again before you take the cap off to check that the PBU went in level.
- Temperature swings with new parts can come from the supply. Kohler says a pressure difference of more than 5 psi between hot and cold causes fluctuations, and that a plumber can measure it with a pressure gauge.
- No water at all? Kohler explains that if only hot or only cold water reaches the valve, the diaphragm inside blocks the outlet, and that these valves need at least 45 psi on both supplies. Make sure both stops are fully open.
Other Kohler shower parts
Older Coralais valves with a square brass stem. Kohler's identifier names these K-15700 or K-15701, and Kohler sells GP77886 as a mixer cap for the older style Coralais pressure balance valve. Our part page lists the K-15700 and K-15701 fit. Our replacement is the cap only.
Three-handle tub and shower valves. On a three-handle Kohler valve, the center handle runs a diverter stem and the outer two are hot and cold stems. Our part pages list the Kohler valves each stem fits, and our guide to water coming out of the tub spout when the shower is on covers the diverter side.
Kohler sink and kitchen faucets. Kohler says the part number of the replacement valve will vary depending on the faucet model number, so start with the model number. Kohler lists where to find it: the product label on the box, the product literature, an invoice or receipt, or stamped on the product itself, and notes the K may be left off. Then enter it in the Find Parts search on Kohler's site. Our cartridge identification guide covers what to look at on the part itself.
When to stop and call a plumber
Each of these is our own advice, not a Kohler rule.
- The PBU will not come out with pliers, or the brass body is scored where the O-rings seal.
- There are no stops on the valve and the main shut-off will not close.
- The temperature still swings with new parts and the cause may be the supply pressure.
- Water leaks from inside the wall, not only from the showerhead or spout.
Frequently asked questions
Do I need the mixer cap and PBU kit, or only the pressure balancing unit?
Kohler's valve identifier for its Rite-Temp valves with a diverter sends a leak to the mixer cap and the pressure balancing unit, and temperature swings to the pressure balancing unit alone. Kohler's dripping guide also says to replace the mixer cap and PBU kit if a drip or leak continues. So for a drip, plan on both parts.
Is the GP876851 kit the same as the GP76851 kit?
Kohler's K-304 service page names the mixer cap and PBU kit GP76851. Ferguson lists the Kohler GP876851 kit as replacing GP76851 and as including the GP800820 unit and the GP77759 cap. Our kit is a replacement for the GP876851.
What grease should go on the O-rings?
Kohler says to use only silicone-based lubricants on these valves and not petroleum-based ones, because petroleum-based lubricants harm the O-rings, seals and plastic parts. Its service page puts silicone lubricant on the small O-rings on the back of the PBU and on the larger O-ring around the cap.
My showerhead drips for a minute after I turn it off. Is the valve bad?
Not always. Kohler says showerheads can drip for up to 90 seconds after the valve is turned off. A drip that keeps going after that is the one to fix.
How hot should the temperature limit be set?
Kohler says the water temperature should never be set above 120 degrees F, and to check it with a thermometer. It also warns that a pressure balancing valve does not make up for changes in the supply temperature, so check the setting again after the seasons change or after water heater service.
Sources
The steps above come from these pages, except where a step says the advice is our own. We opened each one on October 12, 2026. Retailer pages are used for part numbers and fit only where we could not open a Kohler page.
- Kohler, Rite-Temp K-304 Service Part Installation Instructions.
- Kohler, Adjust the Temperature on a Rite-Temp Shower Valve.
- Kohler, Rite-Temp Valve Dripping from Showerhead or Spout.
- Kohler, Identifying Single-Control Shower Valves (1288570-3-C).
- Kohler, Installation and Care Guide, Bath and Shower Valve 1110626-2-K.
- Kohler, Service Kit Instructions 1250244-9-B.
- Kohler spec sheets: K-304-K, K-11748-K and K-8304-KSL.
- Kohler, Finding a KOHLER or STERLING Product Model Number, Leaking from End of Spout and Find a Service Part.
- Kohler, Mixer Cap For Older Style Coralais Pressure Balance Valve, K-GP77886.
- Ferguson, Kohler GP876851 Rite-Temp mixer and pressure balancing unit kit and Kohler GP77759 mixer cap (retailer).
Replacements for the Kohler GP876851 kit, the GP500520 pressure balancing unit, the GP77886 cap and Kohler three-handle stems, plus parts for Moen, Delta, Pfister and more, shipped from Amazon fulfillment centers with Prime delivery.
See the full FourHome assortment on AmazonFourHome is an independent brand and is not affiliated with Kohler Co., Sterling, Ferguson or the other publishers cited. Brand names and part numbers are used only to identify fit or to cite their published instructions. Shut the water off first, do not force the handle or the cartridge, keep the hot limit at or below 120 degrees F, and call a licensed plumber for anything beyond a cap and cartridge swap.
FourHome is not affiliated with or endorsed by any faucet manufacturer. Brand names and part numbers are used only to identify compatibility.