Troubleshooting Guides
P&B Heating & Air Conditioning Corp.
Fujitsu Mini-Split Homeowner Troubleshooting Guide
Congratulations on purchasing a Fujitsu mini split system. Fujitsu has been a leader in the field of mini spit units for decades, and some of the most efficient units in the industry.
Below are some homeowner tips for you to follow when you are having issues with your system:
Look on the bottom right-hand side of all wall mounted indoor units. There you will find three lights Operation, Economy, and Timer. In normal operation the lights will be solid.
If the unit fails to operate, these lights will blink in a pattern. There are several different blink codes, and each one will indicate a different issue with the unit.
The first thing homeowners should do when they have a “blink code”, is to reset the unit.
The unit will not reset by itself so you will need to turn off the power at the circuit breaker.
The blink code can be triggered by a power surge. Turning off the remote will not reset the code.
Leave the breaker off for at least 15 minutes. Then turn the breaker back on and turn on the unit. It should clear the code and work properly.
If the code comes back (Usually within 10 minutes or less) then there is an issue with the unit, and a service tech will need to assess the system.
Other issues that can cause the unit to go into a blink code is a blockage of the outdoor fan. Such as a buildup of snow, ice or debris. If the fan motor has any resistance when it starts to turn the unit senses this and shuts down the unit to protect the motor from damage.
Do not dump hot water on the unit to melt the ice or stick anything inside the unit to try and clear any obstruction. This can cause damage to the unit and void the warranty.
It is also very important not to open the service door and try to repair the unit yourself. The unit is powered with DC current and needs to be discharged properly before servicing. This is very dangerous and needs to handled by a trained technician!
Filter Maintenance
Wall mounted units all have two filters that need to be maintained. Grasp both sides of the access door and pull up gently but firmly.
The filters can be removed by pulling them forward and down.
Wash them in a sink with warm water but DO NOT USE ANY SOAP OR DETERGENTS. Be sure to let the filters dry completely before reinstalling. If you put wet filter in, they will drip and could cause an airflow restriction and cause the unit to ice up in cooling mode or go into a fault.
DO NOT PUT THE FILTERS IN THE DISHWASHER. The hot water will damage them, and it will need to be replaced.
Multizone units
Some Systems are known as a ”Multi zone unit”. This is when you have One outdoor unit connected to two or more indoor units.
When using a multizone system it is important that all the indoor units are in the same Mode (Cool, Heat, Dry, or Fan) A common mistake is having the units in different modes. This will cause the system to go into a fault mode. If this happens follow the steps below.
- Even with the light blinking change all indoor units to the same mode
- Turn off the breaker and wait at 5 - 10 minutes.
- Reset breaker. The unit should then run properly.
If the fault code comes back, call to schedule a service appointment.
Deep Clean
Mini split units can have a mold build up. For this reason, we recommend that indoor units have a thorough deep clean every 3-5 years to keep the units running efficiently.
Wall mounted control
If your unit has a wall mounted control, error codes will be displayed on the control panel. The first thing to do is reset the unit like the instructions above. If the code comes back, call for service.
