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Which is better for Dishwasher? High Loop Drain Line or Air Gap?

Be it Air Gap or High Loop drain line, let's first understand the purpose - the "Why". The rest will be clear for you to make a choice.

So why do we need either of these? These are required to primarily prevent the waste water from flowing back into the Dishwasher or back into your potable/clean water supply line. The waste water could be from your kitchen sink drain or dishwasher. You do not want this waste water flowing back.

How do they do it? As the name indicates, a High Loop Drain Line is a drain line that is looped and set high to disallow waste water from flowing back using basic principles of gravity. Installation is easier and costs less.

On the other hand, Air Gap uses a "gap of air" to accomplish the same by breaking the flow of waste water back into the unit or supply line. It however involves drilling through the countertop to install the airgap unit. It is not only more laborious but the look of airgap through the counter top isn't appealing to everyone. See the picture below that shows both these options.

Airgap vs High Loop Drain Line

Be it Dishwasher, Water Softener or Reverse Osmosis systems, the ultimate goal is to disallow waste water from getting into the supply line. While some of the newer dishwashers have built-in air gap devices, it is important an Air Gap or High Loop Drain Line is put in place as a safeguard. No matter which one you go with, it is important that they are installed properly.

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