New Mitsubishi installation having issues
#1
07-26-20, 11:55 AM
New Mitsubishi installation having issues
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
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
#3
07-26-20, 12:22 PM
@clocert would that be possible even tho it held good vacuum for about 30 minutes when vacuuming it?
We did do a soap test on the valves on the outside unit however we didn't do it on the connections near the inside units because they all ended up being in pretty difficult spots (all inside the wall)
We did do a soap test on the valves on the outside unit however we didn't do it on the connections near the inside units because they all ended up being in pretty difficult spots (all inside the wall)
#4
07-26-20, 12:27 PM
Member
Shouldn’t have installed connections within the walls.
You forgot doing a nitrogen pressure test. And if you didn’t use a micron gauge for the evacuation, that wasn’t done correctly either.
You forgot doing a nitrogen pressure test. And if you didn’t use a micron gauge for the evacuation, that wasn’t done correctly either.
#5
07-26-20, 12:33 PM
Well you are right maybe we shouldn't have but it is what it is.
We didn't do a nitrogen pressure test correct but we did use a micron gauge for the evacuation
What we did do is release some of the gas in the system to do the soap test (after vacuuming) like the instructions said.
We didn't do a nitrogen pressure test correct but we did use a micron gauge for the evacuation
What we did do is release some of the gas in the system to do the soap test (after vacuuming) like the instructions said.
#6
07-26-20, 03:23 PM
Member
Still not good to skip the pressure test.
How long did the system hold a vacuum and how much did it rise? What micron level was achieved?
Mitsubishi wants ~600 PSI pressure test usually, in their commissioning instructions.
How long did the system hold a vacuum and how much did it rise? What micron level was achieved?
Mitsubishi wants ~600 PSI pressure test usually, in their commissioning instructions.
#8
07-26-20, 05:19 PM
@roughneck77
We did vacuumed each line for about 20 minutes and then closed the loop with the gauge on so we could check if it held vacuum we also did this for 20 minutes, all of them didnt rise at all. I honestly am not sure what micron level was achieved. I didn't vacuum it myself we had someone who had this equipment do this. (to make it complicated, it's a friend of my gf's parents who knows a guy who lent him the equipment, and he himself also worked with it before not on A/C systems tho so he helped us with this).
But after checking some more and asking questions in other places as well I feel like you are right and the pressure test puts way more pressure on the system then the vacuuming. We shouldn't have figured that if it holds vacuum there are no leaks.
@clocert
I think yes since we made the holes in the walls a bit bigger so we had enough room to bend the corners nicely and with enough space left to not make it to tight. But I feel based on the comments so far that we really should get someone out here to check it out and fill the system.
ALSO
I did a hard reset again tonight because I found the new error we got strange and just wanted to be sure it would return, it didn't it went away. Actually I was also able to run all 3 units at the same time for an extended amount of time (ran them for about an hour as test) and they didn't turn off on their own anymore. However they also still didn't really cool (yes they are on cooling mode atleast according to their remotes)
We did vacuumed each line for about 20 minutes and then closed the loop with the gauge on so we could check if it held vacuum we also did this for 20 minutes, all of them didnt rise at all. I honestly am not sure what micron level was achieved. I didn't vacuum it myself we had someone who had this equipment do this. (to make it complicated, it's a friend of my gf's parents who knows a guy who lent him the equipment, and he himself also worked with it before not on A/C systems tho so he helped us with this).
But after checking some more and asking questions in other places as well I feel like you are right and the pressure test puts way more pressure on the system then the vacuuming. We shouldn't have figured that if it holds vacuum there are no leaks.
@clocert
I think yes since we made the holes in the walls a bit bigger so we had enough room to bend the corners nicely and with enough space left to not make it to tight. But I feel based on the comments so far that we really should get someone out here to check it out and fill the system.
ALSO
I did a hard reset again tonight because I found the new error we got strange and just wanted to be sure it would return, it didn't it went away. Actually I was also able to run all 3 units at the same time for an extended amount of time (ran them for about an hour as test) and they didn't turn off on their own anymore. However they also still didn't really cool (yes they are on cooling mode atleast according to their remotes)
