A plumbing contractor from Manchester was looking for 30 check valves to go with a commercial boiler system. He required both a low cracking pressure for their reliable opening, and a delivery time of one week. He found 12 check valve listings on the internet that either were a very affordable price point (some) or were from known suppliers but were priced over budget. He decided on a mid range supplier that could provide him with a material test report, a known cracking pressure, and keep its delivery commitment to him. His buying experience reflects how check valves are always affected by price, but only after checking their type, material, and certification first! For example, if a check valve is available for less money, but has a tendency to leak, corrode, and not function as designed – it is a liability and not a bargain!
What a Check Valve Does and Why It Matters
A check valve is a type of valve that allows water, oil, gas, or process fluid to flow in one direction and automatically closes when there’s no flow or when the flow reverses. In plumbing, it helps prevent water from flowing back into the supply line, thus contaminating the drinking water, destroying grinder pumps, or preventing the boiler from priming. The closing mechanism could be a spring-loaded disc, a swinging clapper, a flexible diaphragm or a simple weighted ball, depending on the characteristics of the fluid, the pressure, the velocity of flow and the cracking pressure (the pressure upstream of the valve when it requires the valve to open).
There are some sanitary check valves meant for use in sanitary applications, such as food, beverage, pharmaceutical, and dairy lines; therefore, these sanitary check valves should also include the cleanability requirement. Inside of sanitary check valves must be crevice free, able to drain out, and made out of 316L stainless steel with an electropolished surface finish. Furthermore, elastomer seals used in sanitary check valves must be produced with FDA conformant materials as well. The two check valves used in these heating systems and brewery transfer lines are used to accomplish the same basic task but are manufactured from different types of materials and finishes. Our introduction to what a sanitary fitting is explains the broader category of which sanitary check valves are a key part.
Choosing the Right Type of Check Valve for Your Application
Buying a check valve in plumbing without first clarifying which type fits the job is the fastest route to a leak or a stuck valve. The four most common configurations each suit specific conditions.
| Type | How It Closes | Best For | Watch Out For |
|---|---|---|---|
| Spring‑Loaded Ball or Disc | Spring pushes the ball or disc against the seat | Vertical and horizontal lines; moderate flow rates; fast closing | Can chatter with pulsating flow; sensitive to cracking pressure |
| Swing (Clapper) | Hinged disc swings closed by gravity and reverse flow | Large‑diameter pipes; low‑velocity, steady flows | Must be mounted in correct orientation; not for pulsating flow |
| Diaphragm | Flexible diaphragm seals against a seat | Low‑pressure, sterile, or aseptic applications; slurries | Diaphragm has finite life; periodic replacement needed |
| Lift (Piston) | Disc lifts off seat with forward flow, drops back when flow stops | High‑pressure steam, gas, and water lines; high temperatures | Limited to horizontal installation in many designs |
For plumbing systems — domestic water, heating loops, irrigation — a spring‑loaded brass or stainless steel check valve is the most common choice. For hygienic process lines, a spring‑loaded or ball‑type sanitary check valve in 316L with Tri‑Clamp connections is the standard. The material must match the fluid: brass is acceptable for potable water; 316L is required where chlorinated cleaners or corrosive chemicals are present.
Brand Options When Shopping for Check Valves
The market for check valves includes global fluid power companies, specialist sanitary manufacturers, and general industrial suppliers. Knowing who makes what helps a buyer narrow the field.
- Swagelok (USA): The reference standard for instrumentation and high‑purity check valves. Swagelok’s lift and ball‑check valves are used in laboratories, semiconductor fabs, and chemical plants. Premium pricing, globally available.
- Parker Hannifin (USA): A broad industrial range, from brass plumbing check valves to high‑pressure hydraulic check valves. Strong distribution network, mid‑to‑premium pricing.
- Watts (USA): Dominates the North American plumbing and waterworks check valve market, particularly for backflow prevention and residential/commercial water systems. Mid‑range pricing, widely stocked.
- Dixon Valve (USA): A strong player in industrial hose couplings and sanitary Tri‑Clamp fittings, including stainless steel check valves. Mid‑range, good availability through distribution.
- Alfa Laval (Sweden): Premium sanitary check valves for dairy, brewery, and pharmaceutical applications. The valves are part of an integrated process equipment ecosystem. Premium pricing.
- Eagle Fittings (China): Eagle Fittings is a focused manufacturer of sanitary stainless steel check valves in 316L, with electropolished finishes and full material traceability. The company’s check valve range covers spring‑loaded ball and disc designs, with Tri‑Clamp connections that allow rapid disassembly for CIP cleaning and inspection. Every valve ships with a material test report, surface finish data, and a pressure test certificate as standard. For a buyer who needs a certified, cleanable check valve at a competitive price point — and who values a direct engineering relationship — Eagle Fittings provides a mid‑range alternative to the premium global brands. Our sanitary ball valve collection and check valve range are built for the repeatable, documented performance that food, beverage, and pharmaceutical processors require.
What Does a Check Valve Cost?
When determining the cost of a check valve, we must consider: size, material, connection type, and certification level. For example, a 1/2″ spring-loaded brass check valve will run approximately $8 to $25; however, the cost of a 2″ sanitary check valve made from 316L and finished with electropolish, certification, and tri-clamp connection will be $150 to $400. Although one might believe that size and material account for the price difference between the two products, it is the above-mentioned factors that create additional value for the cost of the valve beyond just metal, including surface finish, documentation, and assurance of no potential for harboring bacteria or corrosion of the valve due to the chemical composition of the clean-in-place (CIP) processing solution being used.
Furthermore, when sourcing check valves, a certified material test report will add cost; however, it will allow the valve to have a higher value than if it was to just be treated as a commodity and allow it to be an auditable component. Eagle Fittings provides an industry-leading solution to sourcing sanitary check valves; in addition to providing a sanitary check valve with complete documentation and at competitive pricing by way of their dedicated supply base and use of efficient manufacturing processes.
Installation and Maintenance: Getting the Valve to Do Its Job
The best check valve will often fail prematurely due to improper installation. Two common problems with check valve installation are trying to mount a swing type in a vertical down run (it will never shut) and trying to install a spring loaded type backwards. The valve body will have an arrow indicating the direction of flow. When you install the valve in a sanitary system, the valve must be able to completely drain of liquid when no flow is present, otherwise there will be a horizontal pocket that can hold liquid and cause contamination. Eagle Fittings supplies three piece Tri-Clamp manufactured check valves that can be taken apart and checked in a matter of minutes with no cutting of the line required.
Periodic inspection of the seat and seal constitutes routine maintenance. Some check valves in plumbing systems will function without maintenance for several years. Elastomer seals in sanitary process lines undergoing daily cleaning-in-place cycles should be checked quarterly, replaced annually, or as soon as there is evidence of swelling or cracking. Having a replacement seat kit on hand will make it possible to turn a repair into a five-minute job.
Check Valve vs. Backflow Preventer: Why the Distinction Matters
Check Valves and Backflow Preventers are frequently misidentified as being two very similar devices. In actuality, the two cannot be substituted for one another due to differences in their function and requirements. A Check Valve is a single stage, unidirectional valve using mechanical means to seal against reverse flow; it does not contain the required components for testing, so it cannot assure zero backflow if damaged or contaminated at the seat. A Backflow Preventer is a more involved system (typically either a double check valve assembly or a reduced pressure zone assembly) and uses two independent check valves, a relief valve, and test ports to function properly; it can be tested to ensure operability, and is required for Cross Connection Control between Potable Water and potential sources of contamination by Plumbing Codes.
In most jurisdictions, a Check Valve does not meet plumbing codes as a Backflow Preventer. In situations that would be considered non-critical (e.g., where Backflow would be an inconvenience and not a health hazard) to the intended use of Potable Water, the installation of a Check Valve would meet the required development of the plumbing system design. In situations that would be considered critical (e.g., where Backflow would create a threat to health/safety) due to the existence of a Potable Water Cross Connection, a listed Backflow Preventer must be installed to meet the required development of the plumbing system design mandated by Plumbing Codes.
Frequently Asked Questions
How much does a check valve cost?
Depending on size, materials, and certification, a check valve can range from $8 to $400+, but typically a ½ inch brass plumbing check valve will sell for $8 to $25 while a 2 inch 316L stainless steel check valve with an electropolished surface and complete documentation can cost $150 to $400. The variations in price reflect differences in materials, surface finish, and certification requirements.
What is the difference between a backflow preventer and a check valve?
A check valve works as a single-stage, uni-directional device; a backflow preventer is an assembly of two independent check valves with a relief valve, and must be tested due to the building code and are required to provide potable water cross-connection control. A check valve by itself does not satisfy the code requirements for backflow preventers in a cross-connection situation.
How to make a homemade check valve?
You can create your own homemade check valve easily using only three components, which include a ball, spring and a seat with low pressure and where it is not necessary to function perfectly. There are no restrictions as to whether you would be allowed to use this design for things like school projects or temporary pumps. However; if you plan on using this type of device in any system that carries drinkable water to your home, then you are encouraged to invest in an ANSI-B16.34 and certified commercial manufactured check valve as a permanent solution.
How much does it cost to have a check valve installed?
The cost of installing a check valve in plumbing will vary depending on both accessibility of the pipe and plumber hourly rates, but will normally run between $80 - $200 per installation. The time taken to install a Tri-Clamp sanitary check valve into a Process Line is minutes and can be performed by in-house Maintenance Staff without the need for special tools.
References
- Watts — Plumbing Check Valves and Backflow Preventers — Product information and application guidance for residential and commercial plumbing.
- Swagelok — Check Valves — Technical data and selection guides for instrumentation and high‑purity check valves.
- Parker Hannifin — Check Valves — Industrial and hydraulic check valve product information.
- This Old House — Plumbing Check Valve Installation — Practical homeowner guidance on where and how to install check valves.
- Family Handyman — Check Valve Basics — Homeowner‑focused articles on check valve selection and installation.
A check valve in plumbing for sale ranges from a $10 brass fitting in a domestic water line to a $400 electropolished sanitary component in a pharmaceutical process. The price difference reflects the material, the certification, and the consequence of failure. A buyer who understands the type, the material, and the documentation required for their specific application can select a valve that does its job — preventing backflow, protecting equipment, and keeping the fluid where it belongs — without paying for a level of certification that is not needed, or worse, buying a valve that is not built for the service. Eagle Fittings supplies sanitary stainless steel check valves for the hygienic end of this spectrum, with the certifications and the traceability that a regulated process demands.
