Roper Dishwasher Drain Hose: High Loop vs. Air Gap for... | appliancefaults.com

Technical Background:

The Roper dishwasher's MCU (Main Control Unit) controls the drain pump relay. When the wash cycle completes or a drain cycle is initiated, the MCU energizes the drain pump relay, sending 120V AC to the drain pump motor. A faulty drain pump, a blocked drain line, or improper hose routing can prevent proper draining. High loops and air gaps are intended to prevent backflow into the dishwasher from the sink drain line.

Symptoms:

US homeowners report that their Roper dishwasher is not draining properly, leaving standing water in the bottom of the tub after a wash cycle. They may also notice unusual gurgling sounds during the drain cycle.

Possible Causes:

Incorrect drain hose system (no high loop or air gap).
Clogged drain hose or garbage disposal.
Defective drain pump.
Partially blocked drain line in the house plumbing.
Air lock in the drain system.

Solution:

1

Inspect the drain hose: Ensure it is properly connected to either the garbage disposal or the sink drain tailpiece. Check for kinks or obstructions.
2

Verify the high loop: Make sure the drain hose is routed as high as possible under the sink counter before connecting to the drain. This prevents backflow.
3

Examine the air gap (if installed): Confirm the air gap is not clogged. Remove the air gap cap and clean out any debris.
4

Test the drain pump: Access the drain pump (usually at the bottom of the dishwasher). Use a multimeter to check for 120V AC to the pump during the drain cycle. If voltage is present but the pump isn't running, the pump is likely defective.
5

Check for clogs: Disconnect the drain hose from the drain port on the dishwasher. Inspect the drain port for any obstructions.
6

Clear the drain line: If the drain line is suspected to be clogged, use a plumbing snake to clear the line.
7

Run a test cycle: After making any repairs or adjustments, run a short test cycle to verify proper draining.

Safety Warning:

Always disconnect power to the dishwasher at the breaker panel before attempting any repairs. Wear appropriate safety glasses and gloves. Dishwashers contain high voltage components.

Prevention:

Periodically check and clean the dishwasher drain filter. Run hot water through the garbage disposal (if the dishwasher drains into it) to prevent grease buildup. Consider using a dishwasher cleaner regularly to prevent clogs.

Expert Tip:

Many Roper dishwashers have a service mode that allows you to manually activate the drain pump. Consult the technical sheet (usually located behind the kick plate) to find the service mode entry sequence. This is useful for testing the pump independently.

Frequently Asked Questions

•How do I access the drain pump on my Roper dishwasher?

Typically, you'll need to remove the lower access panel or kick plate. You may also need to remove the lower spray arm and filter assembly inside the dishwasher tub to access the pump from the inside.

•What voltage should I expect to see at the drain pump during the drain cycle?

You should expect to see approximately 120V AC at the drain pump when it is activated during the drain cycle. Use a multimeter to verify the voltage.

•My dishwasher doesn't have an air gap. Is a high loop sufficient?

In many US jurisdictions, a high loop is sufficient if it meets local plumbing codes. However, an air gap provides the best protection against backflow contamination. Consult your local plumbing codes for specific requirements.

Roper Dishwasher Drain Hose: High Loop vs. Air Gap for US Plumbing Explained

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I access the drain pump on my Roper dishwasher?

•What voltage should I expect to see at the drain pump during the drain cycle?

•My dishwasher doesn't have an air gap. Is a high loop sufficient?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: