City Multi h0 fault code

[Slim R410a]

Hi guys,

I've got a city multi system, PUMY-P140YKM1 outdoor, one of the indoor units PEFY-P32VMS1 shows h0 then controller goes blank. (PAC-YT52CRA) No centralised controller.

Electrician on site has just confirmed there is 240V to the indoor unit.

System was installed by ourselves last year, with another 3x PUMY systems, commissioned by Mitsubishi, so all addressing etc ok, any help on what to start looking at before I go to site? (500 mile round trip)

Many thanks,

[Airconking]

Remote controller isn't talking to indoor PCB. If the system has been running for a period of time then I'd suspect a power cut has caused the problem or you have a faulty PCB. Get your electrician to check power supply's on all indoors and condenser and carry out full system reset. If this doesn't work enjoy your 500mile round trip

[Slim R410a]

Thanks for the reply - I'm travelling to N.London tomorrow so going to call in.
Going to try a full system reset first, I believe this is SW2-2 on the outdoor? Any other steps?

[anil130]

Hi..Slim R410a,
switch off all the power of AC including outdoor units up to 1 minutes and switch on
the power of outdoor units and IDU then the setting will reset automatically.i hope
this will work you..

[Slim R410a]

Went to site yesterday tried reset first, then found no M-Net voltage on the indoor unit. (last indoor in series so only has 1x 1.5mm 2core cable going into terminals M1 + M2)
Found 30Vdc on the next indoor along so looks like a damaged/mouse chewed through M-Net cable somewhere. Guys on site are going to try temporary cable between indoors to confirm when both rooms are next free. (busy hotel)