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  • Smart thermostat needs the C wire, that blue wire that is often not connected on the other end at your furnace. It happened to me

    Your new smart thermostat requires it. You are looking to use an existing unused wire (the blue wire) to provide a common (C) wire connection for your new smart thermostat. Here is a professional step-by-step process to ensure you connect the wires correctly and safely:

    Step-by-Step Process for Connecting the C Wire

    1. Turn Off Power:
    • Before starting any work, turn off the power to your HVAC system at the circuit breaker. Verify that the system is off by attempting to turn on the furnace and air conditioner to ensure they do not operate.
    1. Identify the Wires at the Furnace:
    • At the furnace control board, you mentioned that one of your AC wires is connected to the C terminal. Confirm this connection.
    • You also mentioned that the other AC wires are connected to the Y terminal on the control board. Ensure these connections are secure and correctly identified.
    1. Locate the Unused Blue Wire:
    • Find the blue wire from your thermostat cable at the furnace. You mentioned it is currently terminated and unused.
    1. Connect the Blue Wire to the C Terminal at the Furnace:
    • Connect the blue wire to the C terminal on the furnace control board. Ensure the connection is secure and properly tightened.
    1. Identify the Wires at the Thermostat:
    • At the thermostat location, identify the existing wires and their connections. You mentioned that one of the AC wires is connected to the C terminal on the thermostat.
    1. Connect the Blue Wire to the C Terminal at the Thermostat:
    • Connect the other end of the blue wire to the C terminal on your new smart thermostat. Ensure the connection is secure and properly tightened.
    1. Verify All Connections:
    • Double-check all connections at both the furnace and the thermostat to ensure they are correct and secure.
    1. Turn On Power and Test:
    • Restore power to your HVAC system at the circuit breaker.
    • Turn on your new smart thermostat and follow its setup instructions. Verify that the thermostat is functioning correctly and that the HVAC system responds as expected.

    Additional Considerations

    • Check Compatibility: Ensure your new smart thermostat is compatible with your HVAC system. Refer to the thermostat’s manual for specific wiring requirements.
    • Safety: Always follow safety guidelines when working with electrical systems. If you are unsure about any part of the process, consider hiring a professional electrician or HVAC technician.
    • Documentation: Keep a record of your wiring configuration for future reference or in case you need to troubleshoot any issues.

    By following these steps, you should be able to successfully connect the C wire using the existing blue wire, ensuring your new smart thermostat functions properly.

  • Gable fans (vs attic fans) install from inside the attic.

    Installing an attic fan entirely from inside the attic can be challenging because most attic fans require some external work, such as installing flashing to ensure a watertight seal. However, there are some gable-mounted attic fans that can be installed entirely from inside the attic, provided you have access to the gable wall from inside. Here are a few options with links to product information and Amazon listings:

    1. QuietCool QC ES-1500 Gable Mount Attic Fan

    – Model: QuietCool QC ES-1500

    – CFM: 1488 CFM

    – Features: Energy-efficient, quiet operation, easy installation.

    – Why It’s Suitable for Inside Installation: This fan is designed for gable mount installation, which can often be done entirely from inside the attic if you have access to the gable wall.

    – Product Link: [QuietCool QC ES-1500 on Amazon](https://www.amazon.com/QuietCool-QC-ES-1500-Gable-Mount/dp/B0043M4Q8K)

    2. Lasko 36-Inch Electrically Reversible Window Fan

    – Model: Lasko 36-Inch Window Fan

    – CFM: Not specified, but suitable for smaller attics or rooms.

    – Features: Reversible airflow, adjustable thermostat, easy to install.

    – Why It’s Suitable for Inside Installation: While typically used for windows, this fan can be adapted for gable mount installation from inside the attic if you have a suitable opening.

    – Product Link: [Lasko 36-Inch Window Fan on Amazon](https://www.amazon.com/Lasko-36-Inch-Electrically-Reversible-Window/dp/B000050B2E)

    3. Air Vent Gable-Mount Power Attic Ventilator

    – Model: Air Vent Gable-Mount Power Attic Ventilator

    – CFM: 1620 CFM

    – Features: Thermostat controlled, durable construction, easy installation.

    – Why It’s Suitable for Inside Installation: Designed for gable mount, this fan can be installed from inside the attic if you have access to the gable wall.

    – Product Link: [Air Vent Gable-Mount Power Attic Ventilator on Amazon](https://www.amazon.com/Air-Vent-Gable-Mount-Power-Ventilator/dp/B000BQW68C)

    Installation Tips for Gable-Mount Fans from Inside the Attic:

    1. Access the Gable Wall: Ensure you have access to the gable wall from inside the attic. This might involve removing some insulation or other obstructions.

    2. Cut the Opening: From inside the attic, cut an opening in the gable wall according to the fan’s specifications. Make sure the opening is the correct size and shape.

    3. Mount the Fan: Secure the fan to the gable wall using the provided brackets and screws. Ensure the fan is level and securely fastened.

    4. Connect Wiring: If the fan is electric, connect the wiring according to the manufacturer’s instructions. Ensure all connections are secure and meet local electrical codes.

    5. Seal the Edges: Use caulk or weatherstripping to seal around the edges of the fan to prevent air leaks.

    6. Test the Fan: Once installed, turn on the fan to ensure it is working correctly.

    Additional Considerations:

    – Check Local Building Codes: Before starting, check local building codes and regulations to ensure compliance.

    – Professional Help: If you are unsure about any part of the installation, consider hiring a professional to ensure it is done correctly and safely.

    These gable-mounted fans can be installed entirely from inside the attic, provided you have access to the gable wall. Always follow the manufacturer’s instructions and take necessary safety precautions during installation.

  • Best SOLAR attic fans run and run for free

    When considering the most effective solar-powered attic ventilation fans, several factors come into play, including CFM (Cubic Feet per Minute) rating, durability, ease of installation, and overall performance. Here are some of the top-rated and most effective solar-powered attic ventilation fans available on the market, along with links to product information and Amazon listings:

    1. Remington Solar Attic Fan

    • Model: Remington Solar Attic Fan
    • CFM: Up to 1400 CFM
    • Features: Adjustable solar panel, high-efficiency brushless motor, weather-resistant construction.
    • Why It’s Effective: The high CFM rating and adjustable solar panel make it highly effective for various attic sizes. The brushless motor ensures long-lasting performance.
    • Product Link: Remington Solar Attic Fan on Amazon

    2. Master Flow 1200 CFM Solar Powered Roof Mount Attic Exhaust Fan

    • Model: Master Flow ERV12
    • CFM: 1200 CFM
    • Features: 28-watt solar panel, adjustable thermostat, durable construction.
    • Why It’s Effective: The adjustable thermostat allows for customized ventilation, and the 28-watt solar panel ensures strong performance even on cloudy days.
    • Product Link: Master Flow ERV12 on Amazon

    3. Natural Light Solar Attic Fan

    • Model: Natural Light SA-1
    • CFM: Up to 1000 CFM
    • Features: 25-watt solar panel, adjustable thermostat, weather-resistant housing.
    • Why It’s Effective: Known for its quiet operation and reliable performance, this fan is suitable for medium-sized attics and offers good value for money.
    • Product Link: Natural Light SA-1 on Amazon

    4. Eco-Worthy Solar Powered Attic Fan

    • Model: Eco-Worthy 25W
    • CFM: Up to 1000 CFM
    • Features: 25-watt solar panel, adjustable thermostat, durable aluminum housing.
    • Why It’s Effective: The aluminum housing adds durability, and the adjustable thermostat helps maintain optimal attic temperatures.
    • Product Link: Eco-Worthy 25W on Amazon

    5. Solar Royal SR1800

    • Model: Solar Royal SR1800
    • CFM: 1800 CFM
    • Features: 30-watt solar panel, high-efficiency motor, adjustable thermostat.
    • Why It’s Effective: With the highest CFM rating on this list, the SR1800 is ideal for large attics and offers excellent ventilation performance.
    • Product Link: Solar Royal SR1800 on Amazon

    Key Considerations for Effectiveness:

    • CFM Rating: Higher CFM ratings indicate better airflow, which is crucial for effective ventilation.
    • Solar Panel Wattage: A higher wattage solar panel can generate more power, ensuring the fan operates efficiently even in less-than-ideal sunlight conditions.
    • Adjustable Thermostat: Allows the fan to turn on and off based on attic temperature, optimizing energy use and ventilation.
    • Durability and Build Quality: Fans with weather-resistant and durable materials will last longer and perform better over time.
    • Installation and Maintenance: Ease of installation and low maintenance requirements can contribute to the overall effectiveness of the fan.

    When choosing the most effective solar-powered attic ventilation fan, consider the size of your attic, your local climate, and your specific ventilation needs. The models listed above are highly regarded for their performance and reliability, making them excellent choices for improving attic ventilation.

    The effectiveness of an attic fan in cooling a house can vary based on several factors, including the size of the house, the climate, the type of fan, and the insulation of the attic. However, here are some general insights on how much cooler a house can become with an attic fan running:

    Temperature Reduction

    – Attic Temperature: An attic fan can significantly reduce the temperature in the attic itself. On a hot day, the attic temperature can be reduced by 30 to 50 degrees Fahrenheit (17 to 28 degrees Celsius) compared to not having a fan.

    – House Temperature: The impact on the overall house temperature is less dramatic but still noticeable. You can expect a reduction in the living space temperature by about 5 to 15 degrees Fahrenheit (3 to 8 degrees Celsius). This reduction depends on how well the house is insulated and how much heat is being transferred from the attic to the living areas.

    Factors Affecting Cooling Efficiency

    1. Insulation: A well-insulated attic will prevent a significant amount of heat from transferring to the living spaces below. An attic fan can help keep the attic cooler, which in turn helps maintain the effectiveness of the insulation.

    2. Ventilation: Proper ventilation is crucial. An attic fan works best when there are sufficient intake vents (like soffit vents) to allow cooler air to enter the attic as the hot air is expelled.

    3. Fan Size and CFM: The size of the fan and its CFM (Cubic Feet per Minute) rating will determine how much air it can move. A higher CFM rating generally means more effective cooling.

    4. Climate: In regions with high humidity, the effectiveness of an attic fan might be reduced because the air being pulled into the attic may already be warm and moist.

    5. Roof Color and Material: Darker roofs absorb more heat, making the attic hotter. An attic fan can help mitigate this, but the initial temperature difference will be greater.

    Additional Benefits

    – Energy Savings: By reducing the temperature in the attic, an attic fan can help lower the workload on your air conditioning system, potentially leading to energy savings.

    – Moisture Control: Attic fans can also help reduce moisture buildup in the attic, which can prevent mold and mildew growth.

    Practical Example

    If your attic temperature is around 120°F (49°C) on a hot day without a fan, installing an attic fan could bring it down to around 80-90°F (27-32°C). This reduction in attic temperature can help keep the living areas cooler, potentially reducing the indoor temperature from 85°F (29°C) to around 75-80°F (24-27°C), depending on the factors mentioned above.

    In summary, while an attic fan won’t make your house as cool as air conditioning, it can significantly reduce the temperature in the attic and contribute to a cooler and more comfortable living environment.

  • Holes and Knockouts – Pipes, connectors

    To create knockout holes in electrical panels, several tools are recommended:

    1. Hydraulic punch set: This is one of the best tools for creating clean, precise holes in electrical panels. It consists of a hydraulic pump, punch dies, and draw studs6.
    2. Knockout punch set: These manual punch sets are effective for creating accurate holes in electrical panels. They come in various sizes and can punch through mild steel, aluminum, fiberglass, and plastic23.
    3. Hole saws: These are suitable for drilling holes in panels and come in sizes corresponding to standard knockout sizes4.
    4. Electrical panel knockout kit: This specialized tool is designed to open knockouts without damaging the panel or surrounding drywall1.

    To measure the correct size for a knockout hole in a panel:

    1. Determine the trade size of the conduit or connector you’ll be using. This is the standard label used in the electrical industry.
    2. Refer to a knockout size chart or guide to find the corresponding hole size for your trade size. For example:
      • 1/2″ trade size requires a 7/8″ (22.5mm) hole
      • 3/4″ trade size requires a 1-1/8″ (28.3mm) hole
      • 1″ trade size requires a 1-3/8″ (34.6mm) hole4
    3. Use precise measuring tools like a tape measure or caliper to mark the center point of the hole on the panel.
    4. Consider using a center punch to create a small indentation at the marked point, which will help guide your drill bit or punch tool6.
    5. For multiple knockouts, you can use a layout tool like the Center Point Knockout Layout Tool to quickly and accurately mark the centers of desired conduits5.

    Remember to always follow safety guidelines and use appropriate personal protective equipment when working with electrical panels and tools.

    For beginners creating knockout holes, there are several recommended tools that are easier to use and more affordable:

    1. Manual knockout punch set: This is a good starting point for beginners. It’s less expensive than hydraulic options and allows you to get familiar with the process12.
    2. Hole saws: These are versatile and can be used for various materials. They’re a good option for beginners who may not be ready to invest in a specialized knockout tool2.
    3. Step bits: These are useful for making smaller holes and can be a good addition to a beginner’s toolkit2.
    4. Greenlee Slug-Buster Knockout Punch Set: This manual set is often recommended for its ease of use and effectiveness3.
    5. Klein Tools Knock-Out Punch Set: This is another manual option that’s great for beginners working on smaller projects, like adding a circuit to a box7.

    When starting out, it’s important to practice proper alignment and technique. Many knockout sets come with alignment markings or crosshairs to help ensure accurate hole placement12. As you gain experience, you can consider upgrading to more advanced tools like hydraulic or battery-powered knockout sets.

    Remember to always prioritize safety and follow manufacturer instructions when using any hole-making tools.

    For beginner-friendly knockout tools that are lightweight and easy to use, consider the following options:

    ToolFeaturesWeight/DesignEase of Use
    Greenlee 7238SB Slug-Buster KitManual punch set for 1/2″ to 2″ holes, alignment markings for accuracyCompact and lightweightSimple manual operation with included wrench
    Pittsburgh Knockout Punch KitAffordable manual kit for punching holes in steel, aluminum, and plasticLightweight 10-piece kitIdeal for basic tasks; easy for beginners
    Klein Tools Knockout Punch Set with Wrench3Includes punches, dies, and ratcheting wrench for 1/2″ to 2″ holesCompact design; cuts up to 10-gauge steelClean and accurate punching with manual control
    iTOOLco Gear Punch Kit2Works with any drill, punches 1/2″ to 4″ holes, lifetime warranty on draw studsLightweight and drill-compatibleEasy setup with Center Point alignment tool

    Manual knockout punch kits like the Greenlee or Pittsburgh are cost-effective and beginner-friendly. For added convenience with a drill, the iTOOLco Gear Punch Kit is a versatile option.

    Based on the search results, the most versatile knockout tool for different materials appears to be the Milwaukee M18 FORCE LOGIC Knockout Tool. Here’s why:

    1. Material versatility: It can punch holes in various materials, including mild steel, stainless steel, aluminum, brass, copper, fiberglass, and plastics13.
    2. Punching capacity: The tool can punch up to 4″ holes in 14 gauge mild steel, making it suitable for a wide range of applications4.
    3. Power and force: It delivers up to 10 tons of hydraulic force, enough to punch through tough materials like stainless steel3.
    4. Cordless design: Being battery-powered, it offers more flexibility and portability for working in different environments and tight spaces3.
    5. Quick Connect system: This feature simplifies setup and ensures accurate alignment, making it easier to work with different materials and hole sizes3.
    6. Compatibility: The tool is part of Milwaukee’s M18 battery platform, which adds to its versatility across different job sites and applications3.

    While other tools like the Greenlee knockout sets also offer versatility, the Milwaukee M18 FORCE LOGIC Knockout Tool stands out for its combination of power, portability, and ability to work with a wide range of materials and hole sizes.

  • Standard sizes for the various round electrical panel knockouts

    Electrical panel knockouts and their corresponding hole sizes for drilling come in several standard sizes:

    1. 1/2″ trade size: 7/8″ (22.5mm) hole2
    2. 3/4″ trade size: 1-1/8″ (28.3mm) hole2
    3. 1″ trade size: 1-3/8″ (34.6mm) hole2
    4. 1-1/4″ trade size: 1-3/4″ (43.2mm) hole2
    5. 1-1/2″ trade size: 2″ (49.6mm) hole2
    6. 2″ trade size: 2-1/2″ (61.5mm) hole2
    7. 2-1/2″ trade size: 3″ (74mm) hole2
    8. 3″ trade size: 3-5/8″ (89.9mm) hole2
    9. 3-1/2″ trade size: 4-1/8″ (102.7mm) hole2
    10. 4″ trade size: 4-1/2″ (115.4mm) hole2

    When drilling these holes, you can use either a hole saw or a conduit knockout punch of the corresponding size2. For example, for a 1/2″ trade size conduit, you would use a 7/8″ hole saw or a 1/2″ conduit knockout punch2.

    It’s important to note that the trade size does not directly correspond to the actual hole size. The hole size is typically larger to accommodate the fittings and connectors used with the conduit.

    The difference between ‘trade size’ and actual size in electrical conduit is sigThe difference between ‘trade size’ and ‘hole size’ in electrical conduit and knockouts is significant:

    1. Trade size: This is a standardized label used in the electrical industry to identify conduit sizes. It does not directly correspond to the actual physical measurements of the conduit or knockout3.
    2. Hole size: This refers to the actual diameter of the hole that needs to be drilled or punched for the conduit to fit properly1.

    For example:

    • A 1/2″ trade size conduit requires a 7/8″ (22.5mm) hole1.
    • A 1″ trade size conduit needs a 1-3/8″ (34.6mm) hole1.

    The trade size system was developed to simplify conduit selection and ensure compatibility between components. However, it can be confusing for those unfamiliar with industry standards3.

    Understanding this distinction is crucial for electricians and DIY enthusiasts when selecting the appropriate conduit size and drilling the correct hole size for their specific installation needs. The hole size is typically larger than the trade size to accommodate the fittings and connectors used with the conduit14.

    the hole sizes mentioned for electrical conduit also apply to knockouts needed for connectors and other fittings12. These standardized sizes ensure compatibility between conduits, connectors, and electrical boxes. For example:

    1. A 1/2″ trade size conduit or connector requires a 7/8″ (22.5mm) knockout or hole.
    2. A 1″ trade size conduit or connector needs a 1-3/8″ (34.6mm) knockout or hole.
    3. A 1-1/4″ trade size conduit or connector fits into a 1-3/4″ (43.2mm) knockout or hole.

    This standardization allows electricians to use the same knockout sizes for both conduits and their corresponding connectors, simplifying installation and ensuring proper fit. When working with electrical panels or boxes, the knockout sizes are designed to accommodate these standard trade sizes for conduits and connectors34.

  • Furnace large custom duct collars for large ductboard return

    According to North Carolina building codes, there are specific requirements for constructing duct collars when building a large ductboard supply duct into the furnace:

    1. All connections, including the duct collar, must be sealed with water-based duct mastic1. This is critical for meeting the new North Carolina Energy Conservation Code (NCECC) requirements.
    2. Tape can be used during installation, but should not be relied upon as the primary method of air sealing ductwork1. Mastic should be applied over the tape to ensure airtightness.
    3. The duct collar should be properly sized and well-sealed where it meets the air handler1. This is particularly important due to the large size of plenums, as poor connections at the air handler can lead to significant leaks.
    4. When connecting the ductboard to metal components like the furnace, a metal collar or sleeve should be used to ensure a secure and airtight connection4.
    5. The duct collar must be constructed to meet the pressure class requirements of the system4. Each size in a pressure class has minimum specifications for joints and reinforcements.
    6. Proper support for the duct collar and adjacent ductwork is required. Metal straps with a minimum width of 1 inch (25 mm) and equivalent to or heavier gauge than the duct material should be used for support8.
    7. The duct collar should be designed to allow for proper airflow and minimize pressure drop in the system4.

    Remember to consult the specific North Carolina Mechanical Code and SMACNA guidelines for detailed requirements and best practices when constructing duct collars and connections.

  • Main duct furnace collar examples

  • Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant -It is better than regular water based mastic

    Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant is indeed considered a duct mastic and offers several advantages over regular water-based mastic:

    1. Fiber reinforcement: F-Seal 181 contains fibers that enhance its sealing strength and workability, making it more durable and effective for sealing duct joints12.
    2. UL listings: It is UL 181A-M and B-M listed, indicating it meets strict standards for use with both rigid fiberglass ductwork and flexible air ducts14.
    3. Versatility: F-Seal 181 is suitable for various HVAC applications, including metal ductwork, fiberglass duct board, and flex duct, both indoors and outdoors24.
    4. Performance: It exceeds all SMACNA pressure and sealing classes, providing excellent adhesion and flexibility14.
    5. Additional benefits: F-Seal 181 offers mold and mildew resistance, low VOC content, and contributes to LEED EQ Credit 4.124.

    While regular water-based mastic can be effective, F-Seal 181’s fiber reinforcement and specific formulation for HVAC applications make it a superior choice for many duct sealing tasks. Its fast drying time, excellent adhesion, and ability to seal high, medium, and low-pressure HVAC duct systems further set it apart from standard mastics45

    Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant offers several environmental benefits:

    1. Low VOC content: The product has low volatile organic compound emissions, which contributes to better indoor air quality68.
    2. LEED compliance: It is LEED EQ 4.1 compliant, supporting green building practices and sustainability initiatives8.
    3. Water-based formula: Being water-based, it reduces the use of harmful solvents and is more environmentally friendly compared to solvent-based alternatives6.
    4. Improved energy efficiency: By effectively sealing HVAC duct systems, it helps reduce energy waste and improves overall system efficiency6.
    5. Durability: The fiber-reinforced formula provides long-lasting performance, reducing the need for frequent reapplication and minimizing waste6.
    6. Versatility: It can be used on various duct materials, including metal, fiberglass duct board, and flex duct, both indoors and outdoors, reducing the need for multiple specialized products68.
    7. Mold and mildew resistance: This feature helps maintain a healthier indoor environment and extends the life of the ductwork1.

    These environmental benefits align with Red Devil’s commitment to meeting product demands while helping to preserve the environment and complying with environmental health and safety regulations1.

  • IF Mastic is used to seal an hvac joint, do you still need to tape and mastic the tape?

    If mastic is used to seal an HVAC joint properly, there is generally no need to apply tape and then mastic over the tape. Mastic alone is considered sufficient for sealing duct joints when applied correctly12. Here’s why:

    1. Mastic is more durable and long-lasting than tape, often lasting up to 20 years or longer3.
    2. It creates a flexible, airtight seal that can withstand temperature changes and vibrations1.
    3. For small gaps (less than 1/4 inch), mastic can be applied directly to the joint without additional reinforcement4.

    However, there are some situations where using both tape and mastic might be beneficial:

    1. For medium gaps (1/4-3/4 inch), you can first apply fiberglass mesh tape over the gap, then cover it with mastic4.
    2. When sealing flexible duct connections, some professionals recommend using high-quality duct tape first, then sealing with mastic for added protection2.
    3. In cases where immediate temporary sealing is needed before mastic can fully cure, tape might be used as an initial layer4.

    Remember, when applying mastic:

    • Clean the surface thoroughly before application5.
    • Apply a generous amount, ensuring complete coverage of the joint or seam16.
    • Allow 24-48 hours for the mastic to fully cure3.

    In most cases, properly applied mastic alone is sufficient for sealing HVAC joints without the need for additional taping.

  • HVAC tape ratings ul-181 a-p and ul181b-fx explained

    UL-181A-P and UL181B-FX are important ratings for HVAC tapes, indicating their compliance with specific Underwriters Laboratory (UL) standards:

    1. UL-181A-P:
      • Used for seaming, sealing, and joining rigid fiberglass ductwork (duct board) and sheet metal13.
      • Made of aluminum or aluminum alloy foil with a minimum width of 2.5 inches13.
      • Features an aggressive acrylic adhesive and often includes a release liner3.
      • Designed to withstand the thermal cycles of HVAC systems3.
    2. UL181B-FX:
      • Specifically used for Class 1 flexible air ducts and connectors123.
      • Can be made of foil, film, or cloth with a maximum width of 1.88 inches3.
      • Some UL181B-FX tapes can be used as alternatives to traditional paint-on mastic3.

    Both ratings ensure that the tapes have passed rigorous testing for flame resistance, mold growth, humidity resistance, temperature performance, and other critical factors1. These certifications are crucial for code compliance and guarantee that the tape will effectively seal HVAC systems for their intended lifespan when properly installed3.

    It’s worth noting that a UL181A-P certified product is always certified to UL181B-FX as well, and may carry the designation UL181A-P/B-FX2