Mitsi R2 problem

[Pugwash]

Hi. Have a vrf system with 8 cassettes off bs box but one cassette with it's own remote is going berserk. There is no g50 or bms. All other units run fine set to cool 19, the fan runs on this but has no cooling. Test run it works fine. If you set it to cool 19 after approx 5 mins it either swaps itself to heat 30 or cool 30 but still does no duty. Even if you lock the controller ( par 27) into say cool 30 it still changes itself. Faulty indoor PCb?

[Pugwash]

Meant locked at cool 19 not 30

[Thermatech]

You could just make sure that only this one remote controller is controlling this one indoor unit.
Use the engineers mode at the remote to check configuration of the indoor units & remote controllers.
You need to confirm correct configuration of indoor units & remote controllers as with 30v d/c Mnet PAR27 remote controllers can be connected to any indoor unit but will still only control the indoor units according to address setting.
If 2 remote controllers are controlling this indoor unit & the other controller is in another room then the occupant my be changing it if they dont like cool 19.

If all seems ok then perhaps some electronic fault with indoor circuit board or remote controller.
You could try delete the remote controller using engineers mode & then assume control of the unit with another remote controller in the system & then see if the unit works without this problem. That would be quick & easy & would indicate if problem with indoor unit or remote controller.

[Pugwash]

Fitted new main indoor pcb, cleared faults and all is now good. Thanks for your advice...