Studor Valve Secrets: What Plumbers Won’t Tell You!

Unveiling the Secrets of Studor Valves: What Plumbers May Not Tell You

Studor Valves, also known as Air Admittance Valves (AAVs), are plumbing components that have sparked considerable debate and curiosity.
Often perceived as a shortcut or a "secret weapon" by some, they remain a topic that many plumbers approach with caution, sometimes even reluctance.

Is there a deliberate effort to keep information about Studor Valves under wraps?
Perhaps not a conspiracy, but rather a complex mix of code considerations, application suitability, and professional preferences.
This article aims to demystify these valves, exploring both their benefits and potential drawbacks.

What is a Studor Valve (Air Admittance Valve)?

At its core, a Studor Valve, or more generically an Air Admittance Valve (AAV), is a one-way valve designed to allow air into a plumbing drainage system.
Its primary function is to eliminate the need for extensive vent piping in certain plumbing configurations.

Traditional plumbing systems rely on a network of vent pipes that extend up through the roof.
These vents allow air to enter the drainage system, preventing negative pressure (vacuum) from developing as water flows down the pipes.
This negative pressure, if left unchecked, can siphon water out of the P-traps of fixtures, leading to sewer gas entering the building.

An AAV acts as an alternative air inlet.
When negative pressure develops in the drain line, the AAV opens, allowing air to enter and equalize the pressure.
Crucially, when the pressure returns to normal or becomes positive, the valve seals shut, preventing sewer gases from escaping.

Addressing the "Secrets" and Misconceptions

The perception that plumbers are withholding information about AAVs likely stems from a few factors.

First, AAVs are not universally approved by plumbing codes.
Their use is often restricted to specific situations, and some jurisdictions may prohibit them altogether.
This variability in code acceptance makes many plumbers hesitant to recommend them without carefully evaluating the local regulations.

Second, AAVs are not a "one-size-fits-all" solution.
They are not appropriate for all venting situations, and improper installation or application can lead to problems like sewer gas odors.
Experienced plumbers understand these limitations and may prefer traditional venting methods in certain scenarios.

Finally, AAVs are mechanical devices that can fail over time.
While they can offer convenience and cost savings, they do require periodic inspection and replacement.
Some plumbers may prefer the perceived reliability of traditional vent stacks, which, while more complex to install, are generally less prone to failure.

What We’ll Cover

In this article, we will delve into the practical aspects of Studor Valves and AAVs:

• Installation: Best practices for ensuring a leak-free and code-compliant setup.
• Maintenance: How to keep your AAV in optimal condition and troubleshoot common issues.
• Code Compliance: Understanding the regulations surrounding AAVs and how to ensure your installation meets local requirements.
• Alternatives: Comparing AAVs to traditional vent stacks and exploring other AAV brands.
• Limitations: Identifying the situations where AAVs are not appropriate.

By the end of this article, you’ll have a comprehensive understanding of Studor Valves, empowering you to make informed decisions about their use in your plumbing projects.

What Exactly is a Studor Valve (AAV) and How Does It Work?

Having established the basic concept of Air Admittance Valves (AAVs), let’s delve into the mechanics of how these devices function within a plumbing system. Understanding the physics at play is crucial for appreciating both their utility and their limitations.

It’s important to clarify terminology: Air Admittance Valve (AAV) is the generic term for this type of plumbing fitting. Studor Valve is a specific brand name, much like Kleenex is to facial tissue. While we often use "Studor Valve" colloquially, we’ll primarily use AAV for clarity in this explanation.

Understanding Negative Pressure (Drainage Vacuum)

The heart of an AAV’s operation lies in its response to pressure differentials within the drain lines. When water rushes down a drainpipe, it creates a partial vacuum behind it, a phenomenon known as negative pressure.

Think of it like quickly pulling a stopper out of a bathtub; the water flows out, and air tries to rush in to fill the void. In a traditional plumbing system, vent pipes provide this necessary airflow, preventing the vacuum from siphoning water from the P-traps of other fixtures connected to the same drain line.

An AAV acts as an on-demand vent. Under normal conditions, the valve is sealed shut. However, when negative pressure develops—typically between -0.01 and -0.1 PSI—the pressure differential forces the valve to open.

This allows air to be drawn into the drainpipe, equalizing the pressure and preventing the siphoning action that would otherwise empty the P-traps.

Preventing Sewer Gas Entry

One of the most critical functions of an AAV is to prevent sewer gas from entering the building. Sewer gas, a byproduct of decomposing organic matter in the sewer system, contains methane, hydrogen sulfide, and other potentially harmful or unpleasant gases.

A properly functioning plumbing system maintains a barrier against these gases, primarily through the water-filled P-traps beneath each fixture.

The key here is that the AAV only allows air to flow into the drainpipe, never out. This is achieved through its one-way valve design.

When the negative pressure subsides and the pressure within the drainpipe returns to normal or becomes positive (e.g., due to pressure from the sewer main), the AAV automatically seals shut.

This seal prevents any sewer gas from escaping back into the building, ensuring a safe and odor-free environment.

The Valve in Neutral/Positive Pressure Situations

It’s important to emphasize that the AAV remains closed under normal (atmospheric or neutral) pressure conditions. Also, it stays closed in positive pressure situations such as when sewer gasses may be pushed back into your plumbing system from city lines.

The valve is designed to open only when negative pressure exists within the drain line. This is a critical distinction because it differentiates AAVs from open vent pipes, which are always open to the atmosphere.

The controlled opening and closing of the AAV is what provides the benefits of simplified venting without compromising the building’s protection against sewer gas intrusion. The valve’s responsiveness to pressure changes is key to its efficient operation.

The Hidden Benefits of Studor Valves: What They Offer

Beyond the fundamental mechanics of how AAVs operate, lies a compelling case for their adoption based on tangible benefits. Compared to traditional venting systems, Studor Valves, or AAVs, offer considerable advantages in terms of cost, installation simplicity, and design flexibility. These factors contribute to their growing popularity among plumbers and homeowners alike, particularly in specific applications.

Significant Cost Reductions

One of the most persuasive arguments for using AAVs is the potential for substantial cost savings. Traditional vent stack systems require extensive networks of piping, often running through walls and ultimately terminating through the roof. This translates to significant expenses in terms of materials—pipes, fittings, and roofing materials—as well as the labor involved in cutting, fitting, and installing these components.

AAVs, on the other hand, offer a localized venting solution. This eliminates the need for long runs of vent piping. The reduction in materials directly translates to lower upfront costs. Furthermore, the simplified installation process demands less labor time, further contributing to overall savings. These savings can be particularly impactful in larger projects with multiple fixtures.

Simplified Installation: A Plumber’s Delight

The complexity of installing a traditional vent system can be daunting, especially in renovation projects. Existing walls, structural elements, and limited space often present significant challenges. Cutting through joists, navigating tight corners, and ensuring proper slope for drainage can be time-consuming and labor-intensive.

AAVs offer a significantly simplified installation process. Because they vent locally, they bypass the need for extensive piping networks. This makes them ideal for retrofitting plumbing systems in existing buildings, where running new vent lines through walls and ceilings can be prohibitively difficult or expensive.

Even in new construction, AAVs can streamline the plumbing process, allowing for faster and more efficient installations. This streamlined approach saves both time and money for plumbing contractors.

Unleashing Design Flexibility

Traditional venting systems can impose limitations on plumbing layouts. The placement of fixtures is often dictated by the need to connect to the main vent stack, which can restrict design choices and compromise the aesthetic appeal of a space.

AAVs provide increased design flexibility, allowing plumbers and designers to position fixtures more freely. They can be strategically placed near individual fixtures or groups of fixtures, eliminating the constraints imposed by traditional venting methods.

This newfound flexibility is particularly beneficial in modern homes, where open-concept designs and unconventional layouts are increasingly popular. AAVs enable plumbing systems to adapt to these evolving architectural trends without sacrificing performance or code compliance (where permitted).

Eliminating Roof Penetrations: A Proactive Approach to Leak Prevention

Vent stacks that penetrate the roof are a common source of leaks in buildings. The constant exposure to the elements, combined with the expansion and contraction of materials due to temperature fluctuations, can eventually compromise the integrity of the roof seal. Repairing these leaks can be costly and disruptive.

By eliminating the need for roof penetrations, AAVs reduce the potential for water intrusion. This proactive approach to leak prevention can save homeowners significant amounts of money on future repairs and maintenance. This is especially valuable in regions prone to harsh weather conditions, where roof leaks are a frequent problem.

The Drawbacks and Limitations: Why Some Plumbers Hesitate

While the benefits of Studor Valves (AAVs) are undeniable in certain situations, it’s crucial to acknowledge their limitations. Some plumbers maintain a cautious approach, and for good reason. Several factors can contribute to this hesitation, ranging from code restrictions to concerns about long-term reliability. Understanding these drawbacks is essential for making informed decisions about their application.

Code Compliance: Navigating the Regulatory Landscape

Perhaps the most significant hurdle for widespread AAV adoption is code compliance. Building codes are designed to ensure public health and safety, and venting systems are a critical component. Not all jurisdictions permit the use of AAVs, or they may impose stringent restrictions on their application.

These restrictions often stem from concerns about their performance and longevity compared to traditional vent stacks. Some codes may only allow AAVs in specific situations, such as island sinks or wet-vented fixtures, while prohibiting their use for venting entire plumbing systems.

The final authority on code compliance rests with local Building Code Inspectors. Before installing AAVs, it is imperative to consult with the local building department to verify that they are permitted and to understand any specific requirements or limitations. Ignoring code regulations can lead to costly rework and potential safety hazards.

Potential for Failure: Recognizing the Warning Signs

AAVs are mechanical devices, and like any mechanical component, they are susceptible to failure over time. The internal seal can degrade, become brittle, or become obstructed by debris.

A common symptom of a failing AAV is the presence of sewer gas odor near the fixture. Gurgling sounds in the drain lines can also indicate a malfunctioning valve, as the system struggles to equalize pressure. If these symptoms arise, it is a clear indication that the AAV needs inspection and potential replacement.

Lifespan and Replacement: A Recurring Expense

Unlike traditional vent stacks, which can last for decades with minimal maintenance, AAVs have a finite lifespan. Manufacturers typically estimate a lifespan of between 5 and 20 years, depending on usage and environmental conditions.

This means that AAVs require periodic replacement. This recurring expense should be factored into the overall cost assessment when comparing AAVs to traditional venting methods. It’s crucial to choose high-quality AAVs from reputable manufacturers to maximize their lifespan and minimize the frequency of replacements.

Inappropriate Applications: When to Avoid AAVs

AAVs are not a universal solution for all venting needs. There are specific situations where their use is explicitly not recommended or even permitted.

One crucial limitation is their unsuitability for venting fixtures that handle solid waste, such as toilets. AAVs are primarily designed to vent fixtures that discharge only liquids. The sudden surge of air displacement caused by flushing a toilet can overwhelm the valve’s capacity and potentially lead to sewer gas escaping into the building.

Furthermore, AAVs are not appropriate for venting fixtures that are located a significant distance from the main drain line. In such cases, a traditional vent stack is necessary to ensure proper drainage and prevent siphoning of the P-trap.

Understanding these limitations is vital for selecting the appropriate venting method for each specific plumbing application. A blanket approach, applying AAVs indiscriminately, can lead to performance issues and code violations.

Installation Best Practices: Ensuring a Leak-Free Setup

The long-term effectiveness of a Studor Valve hinges significantly on a meticulous installation. Cutting corners during installation not only negates potential benefits, but also invites premature failure and the very issues the valve is meant to prevent. Proper installation is paramount, not just preferred.

Location, Location, Location: Strategic Placement for Optimal Performance

The location of the AAV is a critical determinant of its efficacy and longevity. Avoid placing it in enclosed, unventilated spaces where moisture can accumulate. High humidity environments accelerate the degradation of the internal components, shortening the valve’s lifespan.

Ideally, the valve should be installed in an accessible area. Future maintenance and potential replacement will be considerably easier. Do not bury the valve behind drywall or in other inaccessible locations.

Consider the potential for exposure to extreme temperatures. While AAVs are generally designed to withstand a range of temperatures, prolonged exposure to extreme heat or cold can affect their performance and durability. Protect the valve from direct sunlight or freezing conditions whenever possible.

Orientation Matters: Vertical is Usually the Way to Go

While some AAV models may accommodate both vertical and horizontal mounting, vertical installation is generally preferred. This orientation facilitates optimal airflow and minimizes the risk of debris accumulation within the valve.

Consult the manufacturer’s specifications to determine the correct orientation for your specific AAV model. Deviating from the recommended orientation can compromise the valve’s performance and void any warranties.

The Imperative of Secure Connections: Preventing Costly Leaks

A leak-proof connection is non-negotiable. Use appropriate thread sealant or Teflon tape to ensure a tight, reliable seal between the AAV and the drain line. Over-tightening can damage the valve body, so adhere to the manufacturer’s torque specifications.

Carefully inspect all connections for leaks after installation. Even a small leak can lead to water damage and promote the growth of mold and mildew. Run water through the drain system to simulate normal operating conditions and check for any signs of leakage.

Accessibility: Planning for the Future

As previously emphasized, the AAV must be easily accessible for inspection, maintenance, and eventual replacement. Consider installing an access panel if the valve is located behind a wall or in a ceiling. This small investment will save significant time and effort in the long run.

Clearly label the location of the AAV to facilitate future maintenance. A simple tag or label can prevent accidental damage or misidentification during plumbing repairs. Document the installation date and model number of the AAV for future reference. This information will be helpful when ordering replacement parts or troubleshooting problems.

Maintenance and Troubleshooting: Keeping Your AAV in Top Shape

While Studor Valves offer convenience and cost-effectiveness, they are not entirely maintenance-free. Neglecting regular checks and maintenance can lead to premature failure and the unwelcome return of sewer gas odors. Proactive maintenance is key to maximizing the lifespan and efficiency of your AAV.

The Importance of Regular Inspections

The first line of defense against AAV problems is regular visual inspection. Aim to inspect your AAV at least twice a year, or more frequently if it’s located in a harsh environment.

What to look for:

• Physical damage: Check for cracks, dents, or other signs of physical stress on the valve body.
• Debris accumulation: Inspect the vent opening for dust, lint, or other debris that could obstruct airflow.
• Signs of moisture: Look for water stains or corrosion around the valve, indicating a potential leak or condensation issue.

Cleaning Your AAV: A Simple Yet Essential Task

Over time, dust, debris, and even grease can accumulate inside the AAV, hindering its performance. Cleaning the valve is a straightforward process that can significantly extend its lifespan.

How to clean:

1. Turn off the water supply to the fixture. This is a crucial step to prevent water from flowing through the drainpipe while you’re working.

2. Carefully remove the AAV. Most AAVs are threaded and can be unscrewed by hand. Consult the manufacturer’s instructions for specific removal procedures.

3. Clean the valve body. Use a soft brush or cloth to remove any visible debris from the exterior of the valve.

4. Clean the valve interior. Gently flush the interior of the valve with warm water. For stubborn debris, you can use a mild soap solution. Avoid using harsh chemicals or solvents, as these can damage the valve’s internal components.

5. Allow the valve to dry completely before reinstalling it.

6. Reinstall the AAV securely, ensuring a tight seal.

7. Turn the water supply back on and check for leaks.

Recognizing the Signs of a Failing Valve

Even with regular maintenance, AAVs can eventually fail. Recognizing the signs of a failing valve early on can prevent more serious problems.

Common symptoms of a failing AAV:

• Sewer gas odor: This is the most common and obvious sign of a failing AAV. If you detect a persistent sewer gas smell near a fixture with an AAV, it’s likely that the valve is not sealing properly.
• Gurgling sounds from drains: These sounds indicate that air is not being admitted into the drainpipe, causing a vacuum that disrupts the water flow.
• Slow draining: A malfunctioning AAV can restrict airflow, leading to slow draining.

Troubleshooting Steps and When to Call a Plumber

If you suspect that your AAV is failing, there are a few simple troubleshooting steps you can try before calling a plumber.

1. Check for obstructions: Ensure that the vent opening is clear of debris.

2. Clean the valve: As described above.

3. Inspect the installation: Verify that the valve is properly installed and that all connections are secure.

If these steps don’t resolve the issue, it’s time to call a qualified plumber. A plumber can diagnose the problem accurately and recommend the appropriate solution, which may involve replacing the AAV.

When professional help is needed:

• If you’re not comfortable working with plumbing.
• If you’re unable to identify the source of the problem.
• If the problem persists after cleaning and inspecting the valve.
• If you suspect a more serious plumbing issue.

Remember, a failing AAV is not just an inconvenience; it can also pose a health hazard due to the presence of sewer gas. Addressing the problem promptly is crucial for protecting your health and the integrity of your plumbing system.

Regular maintenance and prompt troubleshooting are essential to keeping your AAV functioning optimally, but how does it stack up against the traditional plumbing vent systems it aims to replace? Let’s dive into a direct comparison.

Studor Valves vs. Traditional Vent Stacks: A Head-to-Head Comparison

The choice between Studor Valves (AAVs) and traditional vent stacks often hinges on project-specific factors, balancing initial costs with long-term reliability and code adherence. Each system has its strengths and weaknesses, making a thorough evaluation crucial for informed decision-making.

Cost: Upfront Savings vs. Long-Term Expenses

One of the most immediate advantages of Studor Valves is the potential for cost savings during initial installation. Traditional vent stacks require extensive piping to connect fixtures to a main vent line that extends through the roof. This necessitates more materials (pipes, fittings, brackets) and significantly more labor.

AAVs, on the other hand, can often be installed locally at individual fixtures or groups of fixtures, substantially reducing the amount of piping required. This translates to lower material costs and faster installation times, resulting in savings on labor expenses.

However, the long-term cost picture is somewhat more nuanced. AAVs have a finite lifespan and will eventually require replacement. While the cost of a single AAV is relatively low, the cumulative cost of replacements over the lifespan of a building can add up.

Traditional vent stacks, if properly installed and maintained, can last for the life of the building. This minimizes replacement costs, although occasional repairs may still be necessary.

Installation Complexity: Simplicity vs. Established Methods

AAVs shine in situations where installation space is limited or access to traditional vent lines is challenging. They are particularly well-suited for renovations, basement finishing, and island sink installations, where running a vent stack to the roof may be impractical or aesthetically undesirable.

The installation of an AAV is generally straightforward, requiring basic plumbing skills and tools.

Traditional vent stacks, while a well-established technology, can be more complex to install. They require careful planning to ensure proper slope, drainage, and connectivity to the main vent line.

Navigating structural obstacles, such as walls and ceilings, can add to the complexity and labor requirements. Improperly installed vent stacks can lead to drainage problems, sewer gas odors, and potential code violations.

Performance and Reliability: Controlled Airflow vs. Passive Ventilation

Traditional vent stacks rely on passive airflow to maintain neutral pressure within the drainage system. They are designed to allow air to enter the pipes, preventing negative pressure from siphoning water from the P-traps. When properly sized and installed, they offer a reliable and consistent venting solution.

AAVs operate on a demand-based system, opening only when negative pressure is detected. This allows air to enter the drainage system, equalizing the pressure and preventing trap siphonage. While AAVs are generally reliable, they are mechanical devices and can fail over time.

A failing AAV may not open properly, leading to negative pressure in the drain lines and potential trap siphonage. This can result in sewer gas odors and drainage problems. Regular inspection and timely replacement are essential to maintaining the performance of AAVs.

Code Compliance: Location Matters

Code compliance is a critical consideration when choosing between AAVs and traditional vent stacks. Building codes vary significantly from one jurisdiction to another, and some areas may not permit the use of AAVs at all, or may impose specific restrictions on their installation.

Always consult local plumbing codes and building inspectors to ensure that AAVs are allowed in your area and that your installation meets all applicable requirements.

Traditional vent stacks are generally accepted by all building codes, as they are a well-established and proven venting method. However, it’s still important to ensure that the vent stack is properly sized and installed in accordance with local code requirements.

In summary, while Studor Valves offer compelling advantages in terms of cost and installation simplicity, particularly in specific scenarios, it’s crucial to weigh these benefits against potential drawbacks such as code restrictions and the need for periodic replacement. A thorough understanding of the performance characteristics of each system, coupled with careful consideration of local code requirements, is essential for making the right choice.

Addressing the P-Trap Problem: Water Seal Preservation

The unsung hero of plumbing systems, the P-trap, plays a crucial role in maintaining a healthy and odor-free environment within buildings. This simple curved pipe beneath every sink, shower, and toilet contains a water seal, a barrier that prevents noxious sewer gases from backing up into living spaces. While Studor Valves offer numerous advantages in venting, it’s important to understand their relationship with P-traps and how to safeguard the critical water seal.

The P-Trap: Your First Line of Defense Against Sewer Gas

The primary function of a P-trap is to maintain a water seal. This seal effectively blocks the passage of methane, hydrogen sulfide, and other unpleasant and potentially harmful gases from the sewer system into your home or building. Without a functioning P-trap, these gases would freely enter the indoor environment, creating foul odors and posing health risks.

Water Seal Evaporation: The Silent Threat

Even with a properly installed plumbing system, the water seal in a P-trap is vulnerable to evaporation. This is particularly problematic in fixtures that are infrequently used, such as guest bathrooms, seasonal homes, or floor drains in basements. Over time, the water in the trap can evaporate, eliminating the barrier and allowing sewer gas to seep into the building.

Several factors contribute to water seal evaporation:

• Infrequent Use: The most common cause, as water simply evaporates when not replenished.
• Dry Climates: Low humidity accelerates the evaporation process.
• Air Movement: Strong drafts can increase evaporation rates.

Trap Primers: Maintaining the Water Seal

Fortunately, solutions exist to combat water seal evaporation. Trap primers are devices designed to automatically replenish the water in P-traps, ensuring a continuous seal. These devices are connected to a potable water supply and are activated periodically, either by a timer or by a drop in water pressure in the supply line.

There are different types of trap primers:

• Electronic Trap Primers: Utilize a solenoid valve and timer for controlled water release.
• Pressure-Activated Trap Primers: Release water when a pressure drop is detected in the water supply, often triggered by the flushing of a toilet.
• Distribution Manifolds: Can distribute water to multiple traps from a single priming unit.

Trap primers are especially useful in commercial buildings or large residential properties with numerous infrequently used fixtures.

AAVs and Siphoning Prevention: Protecting the Trap

While AAVs themselves do not directly maintain the water seal, a correctly installed AAV can prevent siphoning, another mechanism that can empty a P-trap. Siphoning occurs when negative pressure in the drain line pulls water out of the trap, breaking the seal. AAVs mitigate this risk by allowing air to enter the drain line, equalizing the pressure and preventing the siphoning effect.

The preceding discussion on P-traps highlighted the importance of maintaining a barrier against sewer gases. While a properly functioning AAV helps prevent siphoning that could empty a trap, exploring the wider world of AAVs offers additional options for ensuring optimal plumbing performance.

Beyond Studor: Exploring Other AAV Brands and Options

While Studor is a well-known name, the market offers a variety of Air Admittance Valve (AAV) manufacturers, each with its own features and benefits. Examining these alternatives can lead to a more informed decision based on specific needs and budget.

A Landscape of AAV Manufacturers

Several reputable brands compete in the AAV market. These include Oatey, Sioux Chief, and Keeney. Each manufacturer offers a range of AAVs designed for different applications and pipe sizes.

Oatey is a popular choice, known for its readily available and competitively priced AAVs. They offer a variety of models suitable for residential plumbing.

Sioux Chief provides a comprehensive range of plumbing products, including AAVs engineered for durability and performance in demanding applications.

Keeney focuses on providing innovative plumbing solutions, including AAVs designed for ease of installation and long-term reliability.

Code Compliance: A Non-Negotiable Factor

Regardless of the chosen brand, ensuring code compliance is paramount. Plumbing codes vary significantly by locality, and the use of AAVs may be restricted or subject to specific requirements.

Building codes may dictate the permissible locations for AAVs, the required flow rates, or the need for specific certifications.

Consulting with a local plumbing inspector or a qualified plumber is crucial to verify that the selected AAV meets all applicable code requirements. Using a non-compliant AAV can result in costly rework and potential safety hazards.

Researching and Comparing Options

Selecting the right AAV requires careful research and comparison. Consider factors such as:

• Flow Rate: Ensure the AAV’s flow rate is adequate for the fixture it will be venting.

• Materials: Choose an AAV constructed from durable, corrosion-resistant materials.

• Installation Requirements: Evaluate the ease of installation and compatibility with existing plumbing.

• Warranty: Check the manufacturer’s warranty for peace of mind.

Online resources such as manufacturer websites, product reviews, and plumbing forums can provide valuable insights and comparisons. Consulting with plumbing professionals can further refine the selection process, ensuring the chosen AAV meets the specific needs of the application and complies with all applicable codes.

So, there you have it! Hopefully, you’ve uncovered some secrets about the studor valve you weren’t expecting. Go forth and diagnose plumbing issues like a pro – or at least know what to ask your plumber about that pesky studor valve!