Apollo Backflow Preventers & Check Valves

Apollo 4A Series backflow preventers are among the most widely specified backflow devices in commercial, industrial, and institutional plumbing. Built in the USA and certified to ASSE, NSF, and AWWA standards, Apollo backflow assemblies are trusted on municipal water systems, hospitals, schools, and industrial facilities. PVFPro stocks the full 4A Series line including Reduced Pressure (RP), Double Check (DC), and Pressure Vacuum Breaker (PVB) configurations, plus Apollo 61, 62, and 61Y Series check valves.

Apollo Backflow Preventer Series

4A RP Series — Reduced pressure zone backflow preventer. Highest level of protection — required for high-hazard cross-connections including chemical injection, boiler systems, and irrigation with fertilizer injection. ASSE 1013 listed.
4A DC Series — Double check valve assembly. Approved for low-to-medium hazard applications including commercial buildings, HVAC systems, and non-chemical irrigation. ASSE 1015 listed.
4A PVB Series — Pressure vacuum breaker. Used on irrigation systems and other applications where backsiphonage is the primary concern. ASSE 1020 listed.
4SG Series — Large bore double check valve, grooved end connections. For 2-1/2" through 8" fire protection and large commercial systems.
4AN Series — Large bore flanged backflow preventers with valve setters. For 2-1/2" through 12" municipal and industrial applications.

Apollo Check Valve Series

61 Series — Bronze in-line ball-cone check valve. Spring-assisted, low cracking pressure. 1/4" through 3". Potable water, HVAC, and general service.
61Y Series — Bronze Y-pattern swing check valve. Low pressure drop, suitable for higher flow applications. 1/4" through 3".
62 Series — Stainless steel in-line ball-cone check valve. Corrosion-resistant for chemical or high-purity service.
6SC Series — Cast iron flanged swing check valve. For larger diameter systems, 2" through 16". Industrial and municipal applications.

Applications

Municipal water service protection — required by code on most commercial connections
Hospitals and healthcare facilities — high-hazard RP assemblies for medical gas and chemical systems
Schools and institutional buildings — DC assemblies for HVAC and domestic water
Commercial irrigation — PVB assemblies for above-grade irrigation applications
Industrial process piping — check valves for pump protection and flow control
Fire protection systems — listed backflow assemblies for sprinkler isolation
Boiler and hydronic systems — protection against contamination of potable water supply

Selecting the Right Backflow Device

Hazard Level: High-hazard connections (chemicals, boilers, irrigation with additives) require RP assemblies. Low-to-medium hazard (HVAC, commercial plumbing) typically allow DC assemblies. Always verify with local authority having jurisdiction (AHJ).

Installation Orientation: RP assemblies must be installed horizontally with relief port facing down. DC assemblies and check valves can typically be installed in any orientation — consult the IOM for the specific model.

Testability: RP and DC assemblies require annual testing by a certified backflow tester. Ensure access for test cocks and isolation valves.

Frequently Asked Questions

What is the difference between RP and DC backflow preventers?

RP (Reduced Pressure) assemblies provide the highest level of protection with a differential pressure relief valve between the two check valves. Required for high-hazard applications. DC (Double Check) assemblies use two check valves without a relief valve — approved for low-to-medium hazard connections. Your local water authority determines which device is required.

Do Apollo backflow preventers come with isolation valves?

Yes. Apollo 4A Series assemblies are available in standard configurations with ball valve isolation, OS&Y gate valve isolation, and NRS gate valve isolation options. Test cock configurations vary by model — select the configuration matching your AHJ requirements.

Are repair kits available for Apollo backflow preventers?

Yes. Apollo 4A Series repair kits are available including complete rebuild kits for RP, DC, and PVB assemblies. Find them in our Apollo Service Kits & Spare Parts collection.