Inside view of a Tyco Model A Cover Plate

Tyco's acquisition of Central Sprinkler Company makes replacing Model A Royal Flush Plates difficult, but not impossible

If you’ve landed here, odds are you have Central Sprinkler Company (CSC) Model A, 76A, AA, or A-3 Royal Flush concealed fire sprinklers and need to find replacement cover plates.

Each week, QRFS receives dozens of calls from frantic buyers in need of this product. In this article, we’ll show you what makes the Royal Flush cover plate so unique. We’ll also explain why they’re so rare and help you explore replacement options.

If you'd like to purchase a compatible cover plate now, QRFS carries the following cover plates for Royal Flush fire sprinkler heads:

Tyco acquired Central Sprinkler Company, discontinued cover plates

In the late 1990s, Central Sprinkler Company found itself in financial trouble following a legal battle over their Omega sprinklers. CSC discovered that the Omega sprinkler, which featured an O-ring seal, was compromised over time by corrosion, minerals, salts, and other contaminants that could cause them to fail during an emergency.

Following legal settlements and the recall of nearly 8.4 million Omega sprinklers, CSC was in dire need of capital. Tyco International, one of the world's largest manufacturers of fire sprinklers and fire protection equipment, acquired Central Sprinkler Company in 1999, providing the solution the company needed at that time.

For those with Central Sprinkler Company fire sprinklers and cover plates, this acquisition made it more difficult to find replacement parts. Tyco stopped manufacturing the CSC Model A Royal Flush Concealed Sprinkler—and the corresponding Cover Plate—in 2002.

Cover plates from the RFII, Tyco's successor to Central's Royal Flush fire sprinkler, won't fit original Royal Flush sprinklers

Tyco still offers fire sprinklers that go by the name Royal Flush (or "RF," for short). As you can see, in comparison to the Tyco RFII—the successor model Tyco offers today—the differences are obvious. The Tyco Model A Royal Flush has a larger diameter but reduced depth.

RFII and Model A cover plates compared

A cover plate for the Model A Royal Flush (left) pictured beside the Tyco RFII (right).

The top of the Tyco Model A Royal Flush is about 3 5/8" wide and the base is around 2 5/8" wide. It's also less than 1" tall. On the other hand, the Tyco RFII has a slightly reduced 3 3/8" width and the base is only 2 1/4" inches wide.

Top and inside diameters of model A plate measured

Measurements of the Tyco Model A Royal Flush cover plate.


Measuring tape held to the RFII cover plate from two angles

Measurements of the Tyco RFII Cover Plate.

Fire sprinkler cover plates require an exact substitute

In NFPA 13: Standard for the Installation of Sprinkler Systems, the National Fire Protection Association (NFPA) requires cover plates to be part of a listed sprinkler assembly.

From the 2016 edition of NFPA 13

6.2.7 Escutcheons and Cover Plates. Plates, escutcheons, or other devices used to cover the annular space around a sprinkler shall be metallic or shall be listed for use around a sprinkler. Cover plates used with concealed sprinklers shall be part of the listed sprinkler assembly. The use of caulking or glue to seal the penetration or to affix the components of a recessed escutcheon or concealed cover plate shall not be permitted.

"Part of the listed sprinkler assembly" means that cover plates must be specifically approved for use with a particular sprinkler. These approvals—issued by UL, FM Global (FM), or another certification company—certify that a fire sprinkler head will perform as intended in a specific application. Even a slight mismatch between the cover plate's characteristics and the fire sprinkler head dimish sprinkler system performance or can disable a sprinkler head entirely.

Rare cover plates replace the CSC Model A Royal Flush cover plate exactly, but installing new concealed fire sprinklers is also an option

Two replacement options are available for the CSC Model A Royal Flush concealed cover plate: either replace all of these sprinklers AND cover plates, or purchase Tyco Model A Royal Flush concealed cover plates.

The expense of replacing components within your system can quickly add up. It’s important to remember that all replacements must be performed by a licensed professional. The costs of installing new fire sprinklers include:

  • Hiring a fire sprinkler contractor or fitter to install heads
  • Hiring a designer to ensure that sprinklers have the required characteristics
  • Purchasing fire sprinkler heads and plates
  • Loss of productivity (during installation, parts of the building may need to be evacuated)
  • Inspections by local fire officials

There are many factors to take into consideration when installing or replacing components within a fire sprinkler system such as the sprinkler and cover temperature ratings, coverage area, response time, and more. Failure to account for any of these characteristics can result in failing inspection or increased fire risk.

Click here to read in greater depth about how to replace an obsolete fire sprinkler.

The other and perhaps more feasible option is to purchase a Tyco Model A Cover Plate. These are expensive replacement cover plates, whether you buy them from QRFS or anywhere else. By discontinuing these plates, Tyco has made them more difficult (and costly) to obtain. However, this cover plate meets the temperature ratings of CSC Royal Flush sprinkler heads and fits perfectly.

Fire sprinklers compatible with the Tyco Model A cover plate

Model Orifice Temperature Rating
A 3/8, 7/16, 1/2 155F (68C), 162F (72C)
76A 3/8, 1/2, 17/32 155F (68C), 162F (72C)
AA 3/8, 7/16, 1/2 155F (68C), 162F (72C)
A-1 1/2 155F (68C), 162F (72C)

When you purchase Tyco Model A Royal Flush cover plates from QRFS, you benefit from our competitive pricing, extensive product knowledge, and quick delivery times (generally within 2-3 business days).

If you'd like to purchase a compatible cover plate now, QRFS carries the cover plates for Royal Flush Model A, Model 76A, Model AA, and Model A-3 fire sprinkler heads in three colors: white, grey-white, and chrome.



Questions about our Royal Flush cover plates? Call us at +1 (888) 361-6662 or email [email protected].


This blog was originally posted by Jason Hugo and Cameron Sharp at on May 20, 2016, and updated on January 17, 2019. If this article helped you find a solution, check us out at or on Twitter @QuickResponseFS.