Aaon HVAC Unit RN-025-3-0-BB

Gather necessary cleaning tools and materials

Inspect the drain pan for any visible debris or blockage

Remove any debris from the drain pan

Clean the drain pan with an appropriate cleaning solution

Is the drain line clear and unobstructed?

Ensure all necessary equipment and materials are available

Pump the cleaning liquid through the exchanger

Ensure cleaning solution flow rate is at least 1.5 times the normal flow rate

Rinse the heat exchanger with clean water

Use a solution of 1-2% sodium hydroxide (NaOH) or sodium bicarbonate (NaHCO) before the last rinse

Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.

Check the gas pipe in the unit for leaks before startup.

Disconnect all wiring on the heat exchanger.

Disconnect flex gas lines and pull out of the way.

Remove screws around the perimeter of the heat exchanger face plate that connect it to the unit. Only the outermost screws should be removed.

Pull the heat exchanger straight back and out of the unit. Remove control door jambs if necessary.

Reinstallation of Heat Exchanger

Measure the temperature of the liquid line as it leaves the condenser coil

Read the gauge pressure at the liquid line close to the point where the temperature was taken

Convert the pressure obtained to a saturated temperature using the appropriate refrigerant temperature-pressure chart

Subtract the measured liquid line temperature from the saturated temperature to determine the liquid sub-cooling

Compare calculated sub-cooling to the table below for the appropriate unit type and options

Ensure all necessary cleaning agents and tools are available

Verify the availability of approved cleaning agents

Confirm that harsh chemicals, household bleach, or acid cleaners are not present

Clean the coil with Enviro-Coil Concentrate

Remove any grease or oil film with the approved cleaning agent

Apply CHLOR*RID DTS to the coil