aircon50
21-03-2014, 08:11 PM
Hi guys - thinking caps on please!
I hasten to add that this not my job - I was asked to look at it for an opinion.
System consists of above exterior unit, a ASHA09LACM and ASHA12LACM. The exterior unit PCB has been replaced, as have both EEV's (don't know why?)
From power on the EEV checks can be heard. Switch either interior units on - nothing happens apart from interior fan. There are NO error codes on either interior unit nor on exterior PCB. The situation is the same whether in cool or heat mode.
Disconnect any thermistors from the PCB and the relevant error code is generated on the LED. However, if the pressure switch, compressor thermal switch or EEV's are disconnected there is no error code.
Voltages at terminal strip for power in, and out to interiors are ok, at approx 230vac. There is, from memory, approx 300vac at L1 and L2 on ACTPM for the choke. And again, approx 300vdc at TM104 and TM105 on PCB and corresponding 300VDC at P and N1 on ACTPM.
Questions
What should be seen at communication terminal? I am unsure if it an AC or DC voltage, and if so where is measured across? Or is it something like a modulated frequency that would an oscilloscope?
And is the communication generated by interior, or exterior unit?
Sorry - I don't get to check inverters very often.:confused:
Any information would be greatly appreciated.
Thanks, Graham
I hasten to add that this not my job - I was asked to look at it for an opinion.
System consists of above exterior unit, a ASHA09LACM and ASHA12LACM. The exterior unit PCB has been replaced, as have both EEV's (don't know why?)
From power on the EEV checks can be heard. Switch either interior units on - nothing happens apart from interior fan. There are NO error codes on either interior unit nor on exterior PCB. The situation is the same whether in cool or heat mode.
Disconnect any thermistors from the PCB and the relevant error code is generated on the LED. However, if the pressure switch, compressor thermal switch or EEV's are disconnected there is no error code.
Voltages at terminal strip for power in, and out to interiors are ok, at approx 230vac. There is, from memory, approx 300vac at L1 and L2 on ACTPM for the choke. And again, approx 300vdc at TM104 and TM105 on PCB and corresponding 300VDC at P and N1 on ACTPM.
Questions
What should be seen at communication terminal? I am unsure if it an AC or DC voltage, and if so where is measured across? Or is it something like a modulated frequency that would an oscilloscope?
And is the communication generated by interior, or exterior unit?
Sorry - I don't get to check inverters very often.:confused:
Any information would be greatly appreciated.
Thanks, Graham