DIY HVAC Tools

Tosot mini split code Fo

Refrigerant recovery (pump-down) mode. Also shown as FO.

  • TypeStatus, not a fault
  • SystemDisplay
  • Can I fix it?Usually a homeowner fix

What Fo means on a Tosot

The unit is in its refrigerant-recovery mode, started from the remote, which pumps the charge into the outdoor unit so the line set can be disconnected. The indoor and cooling lamps flash quickly while it runs. Not a fault, but you should not see it unless someone started it.

On this platform, Fo is a status, not a fault: the unit is telling you what it is doing; nothing is wrong.

What to do

You can almost always clear this yourself with the steps below.

  1. If you did not start it, turn the unit off and on with the remote to exit the mode.
  2. If a technician is pumping the system down, leave it alone.

When to call a technician

This is not a fault. No technician is needed unless it will not clear.

Which Tosot units show Fo

This page applies to Tosot Tosot single-zone and Tosot multi-zone units. Tosot's own documentation lists Fo as "Refrigerant recovery (pump-down) mode", the same definition used across the Gree platform it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.

Where Tosot shows this code

The code shows on the indoor unit's display in place of the temperature. If the display is off, press the Light button on the remote. Some models also count out the code as indicator blinks. E codes are system protections and faults, F codes are mostly sensor faults, H codes are outdoor and compressor protections, U codes are motor and valve faults, and P codes are power-supply faults.

Other Tosot codes

Same part of the system as Fo:

H1Defrost cycle runningF7Oil return cycle (cooling)
E1High pressure protectionE2Indoor anti-freeze protectionE3Low pressure protection (refrigerant shortage or blockage)E4Compressor discharge temperature too highE5Over-current protectionE6Communication error between indoor and outdoor unitsE7Mode conflict (multi-zone)E8High temperature protection (overheating)

All Tosot error codes

Fo on other brands

The same characters do not always mean the same thing. Check the brand on your unit.

Questions people ask

Is Fo on a Tosot mini split an error?

No. Fo is a status message: refrigerant recovery (pump-down) mode. The unit is in its refrigerant-recovery mode, started from the remote, which pumps the charge into the outdoor unit so the line set can be disconnected.

Do I need a technician for Tosot Fo?

You can almost always clear this yourself with the steps below. This is not a fault. No technician is needed unless it will not clear.

Sources

  • Tosot owner's manual (error code table)
  • Gree residential split service manuals

Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.