AC Repair Expert.com

Category: Electrical

  • Installing 2 float switches and auto water shutoff

    Installing two float shutoffs to prevent water damage involves setting up a system that automatically cuts off the water supply when the water level reaches a certain point. This setup typically involves connecting the float switches in series to ensure that if either float detects high water levels, the water supply will be shut off. Here’s a detailed process for installing and wiring two float shutoffs:

    Materials Needed:

    – Two float switches (typically with normally open (NO) contacts)

    – Water shutoff valve with a control board

    – Appropriate wire (usually 18-22 AWG)

    – Wire connectors or terminal blocks

    – Screwdriver, wire stripper, and other basic tools

    – Mounting hardware for the floats and control board

    Step-by-Step Installation Process:

    # 1. Choose the Installation Location:

    – Identify the area where water damage is most likely to occur (e.g., near a sump pump, under a sink, or in a basement).

    – Determine the appropriate height for the float switches. The first float should be set at a lower level to act as an early warning, and the second float should be set at a higher level as a backup.

    # 2. Mount the Float Switches:

    – Secure the first float switch at the lower level using the provided mounting hardware. Ensure it is firmly attached and will not move when the water level rises.

    – Mount the second float switch at the higher level, following the same process.

    # 3. Prepare the Wiring:

    – Use wire that is suitable for the environment (e.g., water-resistant if necessary).

    – Cut the wire to the appropriate length to connect the floats to the control board and the control board to the shutoff valve.

    # 4. Connect the Float Switches in Series:

    – Each float switch typically has three wires: a common (C), a normally open (NO), and a normally closed (NC). For this setup, you will use the common (C) and normally open (NO) wires.

    – First Float Switch:

    – Connect the common (C) wire of the first float switch to the power supply (usually a 24V AC or DC source).

    – Connect the normally open (NO) wire of the first float switch to the common (C) wire of the second float switch.

    – Second Float Switch:

    – Connect the normally open (NO) wire of the second float switch to the control board.

    # 5. Wire Color Scheme:

    – Common (C) Wire: Typically black or white.

    – Normally Open (NO) Wire: Typically red or blue.

    – Example Wiring:

    – Connect the black wire (C) from the power supply to the black wire (C) of the first float switch.

    – Connect the red wire (NO) from the first float switch to the black wire (C) of the second float switch.

    – Connect the red wire (NO) from the second float switch to the control board.

    # 6. Connect the Control Board to the Shutoff Valve:

    – Follow the manufacturer’s instructions for connecting the control board to the shutoff valve. Typically, the control board will have a terminal labeled for the float switch input.

    – Connect the wire from the second float switch’s NO terminal to the appropriate terminal on the control board.

    – Connect the control board to the shutoff valve according to the manufacturer’s instructions.

    # 7. Test the System:

    – Turn on the power supply and test the system by manually raising the float switches to simulate high water levels.

    – Ensure that the shutoff valve closes when either float switch is activated.

    – Check all connections to ensure they are secure and that there are no loose wires.

    # 8. Finalize Installation:

    – Secure all wiring with wire ties or conduit to prevent damage or accidental disconnection.

    – Ensure the control board and shutoff valve are properly mounted and accessible for future maintenance.

    Wiring Diagram:

    Code :

     Copy code

    
Power Supply (24V AC/DC)
Black (C)  v
First Float Switch
Red (NO)  v
Second Float Switch
Red (NO)  v
Control Board
(To Shutoff Valve)  v
Shutoff Valve

    Additional Considerations:

    – Regular Maintenance: Periodically check the float switches and control board to ensure they are functioning correctly.

    – Backup Power: Consider installing a battery backup for the system to ensure it operates during power outages.

    – Professional Installation: If you are unsure about any part of the installation, consider hiring a professional plumber or electrician.

  • 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.

  • 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.

  • Why your current thermostat is not using the common wire (C-wire)

    There could be several reasons why your current thermostat is not using the common wire (C-wire) in the wiring harness to the upstairs split heat AC unit:

    1. Your thermostat may not require a C-wire to function. Many older or simpler thermostats, especially non-smart models, can operate without a C-wire as they don’t need constant power3.
    2. The C-wire may be present in the wiring bundle but not connected. Sometimes, the C-wire is left unused and tucked away in the wall4.
    3. Your thermostat might be battery-powered. Some thermostats are designed to run on batteries alone, eliminating the need for a C-wire connection5.
    4. The thermostat could be using alternative power methods. Some smart thermostats can operate without a C-wire by using “power stealing” techniques, drawing small amounts of power from other wires4.
    5. Your HVAC system might not have a C-wire terminal. In some older systems, especially those with only heating, a C-wire may not be available2.

    To determine the exact reason, you would need to:

    1. Check your thermostat’s model and specifications.
    2. Inspect the wiring behind the thermostat to see if there’s an unused C-wire.
    3. Verify the wiring configuration at your HVAC control board.