Install the New Sink Flange — Mount the Air Gap
Part of project
How to Install a Dishwasher Air Gap on a Countertop · Step 3 of 7
In this video
Take a small amount of plumber's putty and roll it into a rope about one-half inch thick. Apply this bead of putty evenly around the underside of the new sink flange. From the top of the sink, insert the flange into the drain opening, ensuring the Kohler logo faces the front of the sink for proper alignment. Press down firmly to create a seal. From underneath the sink, slide the fiber gasket, then the flange, and finally the mounting ring onto the sink flange. Secure these components by pushing the snap ring into the groove on the sink flange. Evenly tighten the three screws on the mounting ring with a screwdriver to pull the assembly tight against the sink. Wipe away any excess putty that squeezes out from the top.
Goal: Mount the new sink flange assembly
- Align the Kohler logo on the flange to face the front of the sink for a professional finish.
- Tighten the mounting screws evenly in a rotating pattern to ensure a level and secure fit.
Used in this video
- Screwdriver (Tool Type: Screwdriver) — Tightening the screws on the mounting ring.
- Rag (Tool Type: N/A) — Wiping away excess plumber's putty.
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FAQs
Is a dishwasher air gap really necessary, or can I skip it to avoid drilling a hole in my countertop?
An air gap is a crucial plumbing safety device designed to prevent contaminated water from siphoning back into your clean dishwasher, especially if the drain clogs. While some local codes allow for a "high loop" drain hose as an alternative, many jurisdictions, like California, still require a physical air gap. Always check your local plumbing codes to ensure compliance and maintain proper sanitation.
Drilling a hole in my countertop sounds intimidating. What type of drill and hole saw do I need, and how can I ensure a clean cut?
For a clean hole, you'll need a powerful drill like the Makita 7 Amp 1/2 in. 900 RPM Drill and a bi-metal hole saw from a kit like the Milwaukee Hole Dozer set, sized correctly for your air gap (typically 1-1/4 to 1-1/2 inches). Start with a pilot hole, use steady pressure, and drill slowly, especially for harder materials like granite or quartz, to prevent chipping. Placing painter's tape on the countertop can also help prevent surface damage.
What are the most common mistakes people make when installing an air gap, especially concerning leaks?
The most common mistakes involve improperly connecting the hoses and not securing them tightly. Ensure all hose connections are seated firmly and secured with stainless steel hose clamps, like the Everbilt 5/16 - 5/8 in. Stainless Steel Hose Clamp. Additionally, apply a small ring of plumber's putty, like Oatey 14 oz. Plumber's Putty, under the air gap's top flange before tightening it down to create a watertight seal against the countertop.
My kitchen design doesn't really allow for an air gap on the countertop. Are there any alternative methods to prevent dishwasher backflow?
Yes, in some areas, a "high loop" installation is an acceptable alternative to a countertop air gap. This involves securing the dishwasher drain hose in a high arch under the sink, ensuring it rises above the flood level of the sink or disposal connection. However, local plumbing codes vary, so it's essential to verify if this method is permitted in your area before skipping the air gap.
Install the New Sink Flange — Mount the Air Gap
Part of project
How to Install a Dishwasher Air Gap on a Countertop · Step 3 of 7
In this video
Take a small amount of plumber's putty and roll it into a rope about one-half inch thick. Apply this bead of putty evenly around the underside of the new sink flange. From the top of the sink, insert the flange into the drain opening, ensuring the Kohler logo faces the front of the sink for proper alignment. Press down firmly to create a seal. From underneath the sink, slide the fiber gasket, then the flange, and finally the mounting ring onto the sink flange. Secure these components by pushing the snap ring into the groove on the sink flange. Evenly tighten the three screws on the mounting ring with a screwdriver to pull the assembly tight against the sink. Wipe away any excess putty that squeezes out from the top.
Goal: Mount the new sink flange assembly
- Align the Kohler logo on the flange to face the front of the sink for a professional finish.
- Tighten the mounting screws evenly in a rotating pattern to ensure a level and secure fit.
Used in this video
- Screwdriver (Tool Type: Screwdriver) — Tightening the screws on the mounting ring.
- Rag (Tool Type: N/A) — Wiping away excess plumber's putty.
Frequently Asked Questions
Is a dishwasher air gap really necessary, or can I skip it to avoid drilling a hole in my countertop?
An air gap is a crucial plumbing safety device designed to prevent contaminated water from siphoning back into your clean dishwasher, especially if the drain clogs. While some local codes allow for a "high loop" drain hose as an alternative, many jurisdictions, like California, still require a physical air gap. Always check your local plumbing codes to ensure compliance and maintain proper sanitation.
Drilling a hole in my countertop sounds intimidating. What type of drill and hole saw do I need, and how can I ensure a clean cut?
For a clean hole, you'll need a powerful drill like the Makita 7 Amp 1/2 in. 900 RPM Drill and a bi-metal hole saw from a kit like the Milwaukee Hole Dozer set, sized correctly for your air gap (typically 1-1/4 to 1-1/2 inches). Start with a pilot hole, use steady pressure, and drill slowly, especially for harder materials like granite or quartz, to prevent chipping. Placing painter's tape on the countertop can also help prevent surface damage.
What are the most common mistakes people make when installing an air gap, especially concerning leaks?
The most common mistakes involve improperly connecting the hoses and not securing them tightly. Ensure all hose connections are seated firmly and secured with stainless steel hose clamps, like the Everbilt 5/16 - 5/8 in. Stainless Steel Hose Clamp. Additionally, apply a small ring of plumber's putty, like Oatey 14 oz. Plumber's Putty, under the air gap's top flange before tightening it down to create a watertight seal against the countertop.
My kitchen design doesn't really allow for an air gap on the countertop. Are there any alternative methods to prevent dishwasher backflow?
Yes, in some areas, a "high loop" installation is an acceptable alternative to a countertop air gap. This involves securing the dishwasher drain hose in a high arch under the sink, ensuring it rises above the flood level of the sink or disposal connection. However, local plumbing codes vary, so it's essential to verify if this method is permitted in your area before skipping the air gap.