Hello Everyone,

I just created an account because we installed a A/C system last weekend in 3 of our upstairs bedrooms and we are experiencing some (strange) issues.

First off our installation contains the following:
- Mitsubishi SCM50ZS-S outside unit, which came charged for 45M of tubing according to the supplier
- 3 Mitsubishi SRK 20ZS-W inside units
- room A has 10 meters of tubing (so 10 for discharge and 10 for suction pipe)
- room B has 6 meters of tubing (so 6 for discharge and 6 for suction pipe)
- Room C has 2.5 meters of tubing (so 2.5 for discharge and 2.5 for suction pipe)

Everything seems to be wired up correctly and we have vacuumed all 3 of the lines beforehand and left them all for about 20 to 30 minutes afterwards to check the pressure of each line if it would drop or not (to check for leaks). Everything seemed fine and we opened up the lines.

We then tested all the systems by turning them on all 3 at the same time and let them run for about an hour. Again everything seemed fine at this point they all cooled and everything was working as expected. This was last Saturday (18th of Juli). Then on Sunday we turned 2 of the 3 rooms on at night and again everything was working perfectly fine.

Then come this week we turned on one of the rooms and it didn't seem to cool really while it ran for a good couple of hours. Because of this I started testing yesterday and turned them on all 3 at the same time again. Only this time I got an error code:

- Timer light on
- Power light blinking 7 times

According to the manual this meant "Refrigerant is insufficient Closed service valve" which seems strange to me since we vacuumed all the lines and it seemed all fine. Also I'm pretty sure that we opened up all the lines.

Then we took the power off today and plugged it back in to give it a hard reset, now we have a completely new error. When we turn on the unit in one of the rooms we it starts running and then after about 10 seconds it shuts off again and displays the following error:

- Timer ligt blinking 4 times
- Power light blinking constantly

Again we checked the manual and this seemed to mean the following: "Broken discharge pipe sensor wire, poor connector connection".

Now I'm not sure what this means or could be since this is a completely new system.
I really was hoping someone here could point me in the right direction on what could be going on. All help would be highly appreciated.


FYI I am in the Netherlands