Sanyo Controller (RCS-SH80AG ) Error 4

Hi Guys

I'm having some trouble with a Sanyo Air Conditioner (1x Outdoor SPW-CR364GVH56 + 2x Indoor Air Handlers), which controller (RCS-SH80AG) is showing Error 4, is flashing “R C 1 - UNIT 1/2" (it alternates between 1 & 2), and has no system operation. This was a working system up until this error.

A quick look at my little code book indicates error 4 is Comms error. So I’ve inspected the comms wire (from the controller to air handling unit 1 to air handling unit 2) and there is no damage.

At this point I isolated the power completely to the whole system and turned it back on. Now the error disappears and the air handler’s strikes up, but after about 5 minutes the error reappears and the air handlers stop. However, in this 5min period I can set the air handler fan speed, and can hear the fans speed up and slow down, so the controller is successfully sending data.

I have had a look at the outdoor unit, which is switch on, has power and I can’t see no obvious problems. However my attention has been cemented inside, as this error occurs on all settings, including “Fan Only”, so I thought this would indicate that the problem can only be inside; am I right to think this?

At this point I’m tempted to replace the controller, but also have a thought that it might be one of the air handling unit PCBs. When I isolate power to just Air Handler 2, I get the same error after 5 minutes of operation, but this time the error is accompanied with “R C 1 - UNIT 1". When I isolate the power to Air Handler 1 there is no power to the controller at all; but I can’t get my head around this, because the comms wire bridges from Air Handler 1 to Air Handler 2, so should be getting power from Air Handler 2?

Any help is appreciated guys!

JV

Hi Rtic,

Error code E04 means the indoor units are not receiving comms from the outdoor unit.

So could be wiring or outdoor PCB.

I'd also check any fuses in the outdoor.

The controller only gets power from one indoor, hence the controller dies when the 'master' is powered off.

Also make sure the outdoor unit is set up for two indoors - it's in the install manual

Cheers

Loops

Hi Loops

Many Thanks for clarifying that for me. I had some time spare yesterday to have a look, and checked the comms the wire from Air handling unit 2 to the outdoor unit, and it’s fine.

I’ve noted that even though there is defiantly voltage to the outdoor unit, and have set the unit up for heating none of the LED lights on the outdoor unit PCB are lighting up.

Indication that the PCB is faulty maybe?