If your refrigerator is not cooling properly, you can try the following steps:

• Check if the refrigerator is plugged in and receiving power.
• Clean the condenser coils to improve cooling efficiency.
• Ensure proper airflow around the refrigerator.
• Inspect the door seals for any signs of damage or leaks.
• If these steps don't solve the issue, consider contacting a professional appliance repair technician.

If your microwave is not heating properly, you can try the following troubleshooting steps:

• Check if the microwave is plugged in and receiving power.
• Ensure the door is fully closed and the safety interlocks are engaged.
• Verify that the cooking time and power settings are appropriate for the food being heated.
• Inspect the internal components, such as the magnetron and diode, for signs of damage.
• If these steps don't solve the issue, consider contacting a professional appliance repair technician.

If your R.O. water purifier is not functioning properly, you can try the following steps:

• Check if the R.O. water purifier is plugged in and receiving power.
• Inspect sediment, carbon, and reverse osmosis filters for clogs, leaks, or damage.
• Check the entire system for leaks, especially around connections and tubing.
• Verify incoming water pressure meets system requirements.
• Inspect the R.O. system's faucet for proper operation.
• Check the reverse osmosis membrane for damage or blockages.
• If water quality is compromised, sanitize the system following manufacturer recommendations.
• If problems persist, seek assistance from a qualified technician specializing in R.O. water purifiers.