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Error Code FYUpdated a year ago

Error Code FY Diagnosis and Troubleshooting

The "FY" code is an error that comes up because the system detects low refrigerant. This can happen on a new install for a number of reasons:

1. The valves on the outdoor unit are not open all the way counterclockwise ↺ (these are what releases the refrigerant from the outdoor unit into the circuit).

2. The length of piping that is being used for the indoor units exceeds the factory pre-charged refrigerant length (25 ft. precharge per zone).

3. There is a leakage somewhere, usually at the connections.
• Look for oil stains or residue around the unit's fittings and connections. 
• Listen for hissing or bubbling sounds near the unit when it's running.
• If the cooling or heating performance is noticeably reduced, there may be a leak.

You can check for leaks by combining water with a small amount of dish soap or liquid detergent:
• Turn on the mini-split unit and let it run.
• Apply this soapy water solution to the fittings, connections, and tubing of the indoor and outdoor units.
• Watch for any bubbles or foaming at the connections.
• If you observe bubbles forming, it indicates a refrigerant leak at that particular spot.

The pressure PSI might need to be checked as well. This is while the system is ON and RUNNING using R410a-compatible gauges, not when it's shut off.

You can force the compressor to turn on using the manual button on the indoor unit. Once it's on, then you can check the pressure and verify that it's within range using our PSI-Temp chart for reference.

Manual button on the Diamante WYT series

Below is a troubleshooting flowchart. If the system is confirmed to be low on refrigerant, you may require an HVAC professional for assistance. 

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