Why does my second unit sometimes start up unexpectedly on a Daikin split system?
Firstly forgive me im a noob in this space, I may get some terminology wrong, but I have been down the channels of trying to get help from the installers and from Daikin direct and I need some expert advice.
I have a problem, that is a little difficult to explain, on the face of it looks like a mode conflict error but it is not.
I hope someone out there has experienced this because according to Daikin and my installer I have a completely unique problem. Which I suspect is not right.
Here goes:
I have a Daikin outdoor Air source heater / cooler compressor (can take up to 5 aircon units) I have two ducted aircon Daikin Sky Sir units connected to it.
Loft - 3.5 kw
Kitchen - 6kw
I have Madoka wall wired thermostat controllers for each.
Symptom
Ever since the install I have a strange situation where 'Sometimes' the kitchen unit turns and heats when the loft unit is turned on, never the other way around.
When it does this the unti is not controllable by its local Madoka or Madoka App, it is pumping out hot air, it show nothing of note onscreen other than the conflict symbol (which you would expect) but it should not turn itself on.
How to replicate the issue
This happens when the units are in different modes to each other, regardless of whether the kitchen unit is on or not.
I can also fix the this problem temporarily by running the kitchen unit in the same mode as the loft for a period of time, sometime 5 mins, sometime an hour.
When it is fixed, the kitchen unit NEVER comes on unless I change the mode (Even if it is off)
I have proven that I can get the unit into a mode where the kitchen does not come on at all and also break it by changing the kitchen mode.
Troubleshoots and other info
Daikin are not interested in helping they said initially that this was design behaviour as the loft unit was too small for the compressor and needs to vent of pressure to other unit on the circuit, hence the kitchen unit turns on. BUT if that were true it would happen every time I run the loft unit and it clearly doesnt.
And if it was default behaviour it is a terrible design
The installers have never seen this issue before, they are a fairly sizeable company and have done thousands of installs. They mainly install Daikin.
We have been through all combinations of field settings and there is nothing seemingly out of place. No units are set to master, they are not setup as groups.
I hope that someone out there has seen something like this before OR has something for me to try. Maybe a full system reset?? no-one seems to know how to do that.
Many thanks in advance.
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