Mitsubushi heavy industry srk25zd-s not working reliably

[rt29781]

Hi, one of our aircon units will start up but then stops. There is no run light. In aircon mode it does come on and works for a few minutes. In heating mode the slats open but then it does nothing.

We have 2 of these machines so I could swap parts to see if I can trace the fault.

Where should I start? What is most likely to have failed?

[goldpau]

check refrigerant charge, its probably empty!

[bigor_2]

http://www.mediafire.com/view/?73hcu0nalergima

[bigor_2]

For self-diagnosis use this link http://www.mediafire.com/view/?73hcu0nalergima

[rt29781]

Many thanks for the advice so far. If it is the refrigerant I will have to get a man in, I will see if I can get any stored codes before I do that probably at the weekend.

[rt29781]

For self-diagnosis use this link http://www.mediafire.com/view/?73hcu0nalergima I turned the mains power off waited 1 minute, and pressed the backup button and turned the power on, wall unit beeped, but got no service lights on run lamp or timer lamp. That display does not light up at all any more. Any suggestions. If I turn the power off then unit works : with temp 21c, fan speed med and in cooling mode the unit will operate and cool. with temp 27c, fan speed med and heating mode unit operates for 2 mins then stops.

[rt29781]

I turned the mains power off waited 1 minute, and pressed the backup button and turned the power on, wall unit beeped, but got no service lights on run lamp or timer lamp. That display does not light up at all any more. Any suggestions. If I turn the power off then unit works : with temp 21c, fan speed med and in cooling mode the unit will operate and cool. with temp 27c, fan speed med and heating mode unit operates for 2 mins then stops.

Took outer cover off found dust obscuring run light. Put into service mode, then set with temp 21c, fan speed med and in cooling mode, gives codes 2 green (run light) and 3 yellow (timer) which the manual suggest is :
operation valve closed or
compressor output open phase or
Electronic expansion valve faulty or
insufficient refrigerant

Any comments anyone?
Is there a simple way I can check refrigerant charge?

[install monkey]

http://www.mediafire.com/view/lzqz2j3nv3w6e27/O%26amp%3BM_RAC_-_SRK.pdf
page 2o gives fault codes