mitsubishi VRF servicing

[moondawn]

hi there,

i have a lot of mitsi vrf equipment to service, The condensors there are 4 in total and 2 of these are twinned together ie 4 condensors and 2 systems.
the equipment is in lots of buildings and most units are centrally controlled. i think i now can gain access to the AG150.
To check units have required gas amounts really i need to test all the units running together this is not so easily done from local remotes.

So is my best option to flick a dip on the outdoor condensor to TEST RUN if so what else can i look for from outside board??

compressor shell temp
discharge temp etc???

looking for a detailed run down if possible so i can give the best possible maintenance to the client

cheers lee

[stufus]

If they are all connected to an AG150 just switch everything onto test from there .Just about every sensor in the system is readable from the outdoor board including accumulator levels and all solenoid activity .The dip switch settings are in the service manuals.
I'm probably stating the obvious here but make sure all the filters and coils are clean before starting to take any readings.
Ideally you need to get your hands on the maintenance tool ,take's a lot of the leg work out of it.
Cheers
Stu

[moondawn]

hi stufus

yeah monitoring tool would be ideal my collegue at work has this but its his personal one. (not sure he would let it out of his sight its took him years to get hold of it)
not gained access in to the AG150 controller as yet, did not know the passcode. I am making sure i clean all coils filters etc before taking these readings.

[JoeAT50A]

You could able to test run from outdoor unit by switching on SW3-1 and SW3-2.
SW3-1 is to activate test-run mode, SW3-2 is On/Off entire system with last memory cum settings.

By using dipswitch SW1, you could able to find most readings (same as Maintenance Tool).
But different series have slight different in SW-1 settings.. of course some are same.
Here is examples.. try it.
6564

[moondawn]

hi joe yeah will look into going through the sw1 dips just really after checking the refrigerant charge is okay as there does not seem to be errors on the equipment as yet

cheers lee

[marc5180]

Personally I think one of the best sensors to check quicky on a routine maintenance visit is the compressor discharge temp as 9 times out of 10 when this is high (100+) you know you have a problem regarding flow back to the compressor wether that be refrigerant charge or even an LEV3 problem in the BC box.

Also if this is low compared with the discharge pressure saturated temp then you will start to get 1500 overcharge faults, caused by either overcharge or high to low bypass with a stuck open LEV

[moondawn]

thanks marc something to check for will check discharge superheat.