My fujitsu a/c unit is not cooling anymore (or much less than in the past). The filters are clean but one of the conduction to the outdoor unit is frozen. do i have to clean the outdoor unit ?

I have found that with my Fujitsu Halcyon, it needs to be disconnected from the mains at the breaker for 2 hours to properly reset. Use that time to clean the filters in the wall unit. The clicking you hear is self testing of relays.

Error code e11 is a communications error. The causes listed in the manual for the outdoor unit are:
1) Connection failure.
2) External cause
3) Main PCB failure.
4) Active filter module failure.
5) Transistor PCB (IPM) failure.
6) Filter PCB failure
7) Outdoor unit Fan motor failure

For the indoor unit the listed causes are:
1. Connection failure
2. External cause
3. Controller PCB failure

With any luck you will have a wiring problem(loose/broken wire). Unfortunately it is more likely to be the Main PCB. Good luck!

Serial signal reverse error. Basically the outdoor unit is not talking to the indoor unit. This is normally due to damage to the outdoor controller PCB and it needs to be replaced.

If there is 3 indoor units from one condensing unit
(6 pipes at outdoor unit) this is classed as a multi unit

All units will run correctly as long as they all require same mode, cooling or heating, if one unit decides to heat it will shut down until master unit decides to heat then it will start, for each unit to individually heat and cool there would have to be 3 pipes to each indoor,

did you try to set to maximum heat? (suspect the thermostat is defective)

If the operation button is flashing 8 times, the timer light should also flash 4 times in each sequence. This indicates a failure of the PFC circuit in the outdoor unit which basically means a faulty outdoor board and will have to be replaced.
If the operation light is flashing 8 times by itself, the indoor controller board may have a fault. You can normally test this by putting the mode on the remote to 'Fan' and checking that the controls otherwise work normally - louvers work as directed and fan speed changes correctly when selected on the remote.
Most likely the fault lies in the outdoor board but you should contact a tech to diagnose correctly.

To get proper cool, keep the tips as follows:
1. Check air filter is cleaned. 2. Check indoor coil is cleaned. 3. Checkindoor blower motor is working. 4. Keep in cool mode. 5. Set temp minimum 3degrees less than room temp.6.Check compressor is working with correctpressure.
Thanks. Helpful?

E3 Outdoor activation of high pressure switch.

Check condenser coil. If blocked, clean it. If out door fan rpm less replace capacitor. Helpful?

Does it get cold? You can try cleaning the fins-both inside and outside, with windex. Smoling & cooking will create a sticky deposit that will make dist that gets through the filter stick and it won't cool properly.
If it doesn.t get cold any more, try replacing the starting capacitor. About $5. If that doesn't take care of it, just replace the unit. They are cheap enough these days, that you can replace a unit with a more energy efficient unit for the same cost or less as a repair would cost.

It appears to be either low on refrigerant or the condenser unit outside is extremely dirty. Make sure you have a clean filter and the you take a garden hose with a sprayer and clean the outdoor coils real good. It should take you no less than 20 minutes to clean them well. If you are done in less time, they aren't clean enough. You should spray the water while the unit is running so that the water is pulled into the unit thus cleaning better. If this doesn't solve your problem then it is low on refrigerant.