How to Match the Right Cartridge to an Older Delta or MultiChoice Valve

Choose RP19804 for an older Delta Monitor 1300/1400 valve configuration and RP46074 for a later 13/14 MultiChoice valve. Delta states that the cartridges are not interchangeable, so identify the installed valve generation or removed cartridge before ordering. Date and color can help, but neither should be the only test.

The short answer: choose by valve generation

Installed valve configuration	Replacement cartridge
Older Monitor 1300/1400 valve	RP19804
Later 13/14 MultiChoice valve	RP46074

Delta’s cartridge instructions label RP19804 as the 1300/1400 cartridge and RP46074 as the 13/14 MultiChoice cartridge. They also identify a removed RP19804 by a white cap and RP46074 by a gray cap—and explicitly state that the two cartridges are not interchangeable. See Delta’s cartridge identification and installation instructions.

Both cartridges sometimes appear under the broad Monitor 1300/1400 name in Delta support material. That grouping does not establish that they fit the same valve housing. The cartridge-specific instructions separate the older 1300/1400 configuration from the later 13/14 MultiChoice configuration.

Despite the name, we do not sell cartridges; we help readers identify the correct part before obtaining it.

RP19804 vs RP46074 comparison table

Cartridge	Matching valve family	Delta date context	OEM cap or color clue
RP19804	Older Monitor 1300/1400	Prior to 2006; Delta’s product title also specifies April 2006 and earlier	Removed original may have a white cap; a current replacement may be blue and white
RP46074	13/14 MultiChoice	MultiChoice valves after 2005	Gray and white; Delta’s cartridge instructions identify a gray cap

Delta assigns RP19804 to valves made prior to 2006 and RP46074 to MultiChoice valves made after 2005. It also says a current RP19804 may be blue and white even when the removed original is all white; that manufacturing color change does not prevent its use as the replacement. Delta’s 1300/1400 guidance provides the date and color context. Delta’s RP19804 product title separately describes it as the cartridge for 1300/1400 Series valves from April 2006 and earlier.

Use color as supporting evidence, not as a substitute for valve identification. The strongest documented clues are the cartridge number, valve family, rough-in or trim model, and the characteristics of the original cartridge.

RP19804 and RP46074 cannot be compared reliably by measurement using the Delta documents cited here. Those documents do not list exact overall lengths, diameters, inlet spacing, leg spacing, or valve-housing dimensions for the two cartridges. Do not treat measurements from look-alike listings as manufacturer-confirmed compatibility specifications.

Treat 2005–2006 as a transition clue, not a date-only test

Delta’s date descriptions overlap: RP19804 is associated with valves made prior to 2006, while the official product title extends the description through April 2006. RP46074 is associated with MultiChoice valves made after 2005.

That makes 2005–2006 useful context, not a clean cutoff for every installation. The year a house was built is especially weak evidence.

For a valve near the transition, confirm the choice using at least one stronger identifier:

• The original cartridge removed from the valve
• Installation instructions, invoices, or saved packaging
• A valve, trim, or rough-in model number
• Molded or stamped numbers on the cartridge
• Delta’s product- and parts-identification resources

“Pre-MultiChoice” is convenient shorthand for the older RP19804 arrangement, but Delta’s cartridge instructions call it the 1300/1400 cartridge configuration. Use the manufacturer’s valve-family description when matching the part.

Likewise, an estimated remodeling date cannot show whether the rough-in body was changed or only the visible trim was replaced.

A practical identification flow before ordering

1. Check the paperwork. Look for installation instructions, invoices, saved packaging, and model or rough-in markings. A documented model number is stronger evidence than an estimated installation year.

2. Do not choose from the trim alone. Similar handles and escutcheons can be installed over different valve generations. The broad Monitor name also appears in material involving both cartridges, so that name alone does not settle which housing is behind the wall.

3. Shut off both water supplies before exposing the cartridge. Turn off the hot and cold supplies, open the valve to relieve pressure, and verify that water flow has stopped before disassembly.

4. Inspect the removed cartridge. A white-capped original supports RP19804, while a gray cap supports RP46074. A blue-and-white replacement can also be RP19804. Use these colors to confirm other evidence rather than allowing color alone to decide the match.

5. Record every useful detail. Photograph the cartridge from several angles, photograph the exposed valve housing, and write down every molded or stamped number. Compare those details with Delta documentation. If the architecture remains unclear, follow a general shower-valve identification process before selecting a cartridge.

If the original cartridge is missing, do not create a fit test from unsupported dimensions. Use the visible valve details, model documentation, and Delta’s parts-identification resources. If the housing still cannot be identified confidently, ask a qualified plumber to inspect it before ordering or installing a cartridge.

Avoid disassembling the old cartridge solely to compare its internal pieces. Delta’s instructions warn against separating the cartridge cap and lower housing and state that the lower housing should never be taken apart. Identification should focus on the complete cartridge and compatible valve body.

Do not force a cartridge that does not fit

A correctly matched cartridge should press into its intended body with its keys aligned to the corresponding slots. If the cartridge stops short, binds, sits proud of the housing, or requires unusual force, stop and recheck the valve generation and part number.

Do not trim the cartridge, alter its lower sections, or force it into the valve body. Delta’s statement that RP19804 and RP46074 are not interchangeable means one should not be adapted to substitute for the other.

Abnormal operation after installation—such as continuous flow, cold-only water, or failure to shut off—can indicate a selection or installation problem, but those symptoms do not conclusively identify the cause. Shut the water off again and verify the cartridge, its orientation, and its seating before proceeding.

Reversed hot and cold can have a different explanation. Reversed supply connections or a back-to-back installation may require the complete pressure-balancing cartridge to be rotated 180 degrees, with the side marked “Hot” remaining at the hot-water supply. Follow Delta’s back-to-back installation instructions rather than assuming that reversed operation proves the cartridge model is wrong.

Remove and reinstall the cartridge safely

Before disassembly, shut off the hot and cold supplies, operate the control to relieve pressure, and confirm that flow has stopped. Remove the handle and sleeve as applicable.

Use the extraction method intended for the installed cartridge:

• RP46074: Delta permits placing a flat-head screwdriver in the notch in the cartridge cap and turning it to raise the cartridge from the body.
• RP19804: Do not pry the cartridge from the valve body with a screwdriver. Reinstall the handle on the brass stem, rotate counterclockwise, and lift the cartridge from the two side notches.

After reassembly, restore the supplies, flush the system, inspect for leaks, and confirm that cold water flows first as the handle opens. Delta also instructs users to adjust the rotational limit stop so the outlet does not exceed 120°F or the lower maximum required by local plumbing code. These identification, extraction, installation, and temperature-limit steps appear in Delta’s cartridge instructions linked earlier.

Pressure balancing reduces outlet-temperature changes caused by changes in inlet pressure, such as another fixture drawing water. It does not automatically compensate for changes in incoming water temperature. Delta therefore directs users to verify the rotational limit stop again if seasonal supply temperatures or water-heater settings change, as explained in the 13/14 MultiChoice owner’s manual.

Because flushing water may be hot, keep hands and tools clear of the outlet stream. If the valve body moves while the bonnet is being loosened, or the cartridge cannot be removed without excessive force, stop and have the installation inspected.

Frequently asked questions

Can a blue-and-white cartridge still be RP19804?

Yes. Delta says a current RP19804 replacement may be blue and white even when the original cartridge removed from the valve is all white. The color change does not prevent the newer RP19804 from replacing the older white RP19804.

Use the part number and older 1300/1400 valve configuration as the primary evidence. Color should confirm the identification, not override conflicting model or valve information.

Does Delta publish exact dimensions for RP19804 and RP46074 in the retrieved documents?

The Delta documents cited in this guide do not provide exact cartridge length, diameter, inlet spacing, leg spacing, or valve-housing dimensions for a reliable measurement-based comparison.

That does not mean the cartridges are dimensionally identical. Delta directly says they are not interchangeable. It means that no manufacturer-confirmed dimensional fit test is provided here, so dimensions from secondary listings should not replace identification by valve family, part number, or original cartridge.

Can seats and springs fix a dripping older 1300/1400 valve instead of replacing the full cartridge?

For a 1300/1400 Series valve that drips from the shower head or tub spout while the handle is off, Delta says replacing the RP4993 seats and springs or replacing the complete cartridge can resolve that specific problem. This recommendation applies to that defined dripping condition; it does not automatically diagnose weak flow, temperature-control trouble, a damaged valve body, or every other leak. See Delta’s repair guidance for a 1300/1400 drip.