MALFUNCTION ANALYSIS

No power supply

Fuse is burned out

Supply voltage is too low

Switch is broken down

Switch is at the OFF position; or socket and plug is

loosened; or power wire has malfunction; or power failure

Replace the fuse

Inspect the supply voltage. If it is lower 10% of the rated

voltage, pleaselook for the reason, improve the

Check if optional switch (ON,OFF) is disconnected with the wire or it’s with mechanical failure; use the universal meter to check if contacts of the switch are conducting; if not, replace

it with a new one with the same model and specifi cation

A/C can’t run

Failure of crystal oscillator or reset circuit

The wire is loosened

Transformer is broken

Controller is broken

Receiver head is loosened

Receiver head is broken or it isn’t plugged well

Replace those parts which have malfunction

Check the circuit and connect the wire according to the

electric diagram attached to the unit

Replace the transformer

Replace the controller

First press the “AUTO” button of the manual switch. If the button is normal, recheck if the installation and connection of head and lines are correct. If correct, replace receiving head or remote controller.

Remote controller has malfunction

A/C can run but it can’t cooling (or heating)

The thermostat hasn’t been adjusted well

Too much dust accumulated on the fi lter

Heat exchanger is blocked

Fan speed is set too slow

Lower the temperature of the thermostat (or increase the temperature when heating)

Clean the fi lter

Clean the dust accumulated on the surface of the heat

exchanger

Set the fan speed at high or medium fan speed

 

 

 

1. Wrong wire connection; 2. whether the capacitor

 

 

 

The fan can’t run or the fan speed is too slow

 

damaged or not; 3. the motor has malfunction; Connect the

 

 

 

 

 

wire correctly or replace those parts which has malfunction.

 

 

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Friedrich PTAC - R410A service manual Malfunction Analysis, Fan can’t run or the fan speed is too slow