Daikin VRV 3 pipe changing mode

[VRVIII]

This is the problem with Daikin VRV.

In aplication like hotel when access to all indoor units is always a problem then you really need to be able to get data from each indoor unit like,,, mode / set temp / EEV opening / return air temp / gas & liquid refrigerant temps from a remote location.
If other manufacturers VRF system is used you can get all that data from every indoor unit by service engineer setting at the outdoor circuit board & outdoor circuit board LED display.
No need for any service checker laptop computer.

The outdoor unit compressor slow down for pressure equalisation every time an indoor unit changes mode has been a big disadvantage for the VRV system.
Look at the new BSV box & you will find that instead of soleniod valves there is now 5 EEV valves !
Trouble shooting any problem with the new BSV boxes without the service checker I suspect will be an even larger challange.

Theratech,

Your obviously a Mitsi man at heart .
But you can’t blame the equipment if you encounter limited access to indoor units; personally I think it’s a case of which ever equipment you are most familiar with and personal preference, Daikin also has a lot of plus points over Mitsi and vice versa. Most of the engineers I know say Daikin VRV is far easier and quicker to commission (I can see a poll being started here).
The fault finding process obviously differs between manufactures and a Daikin service checker is only a tool that allows you view and record all operation data simultaneously but as with any tool it’s only as good as the engineer using it.

The current VRVIII heat recovery system no longer has to equalize when a bs box changes mode, this is now done by slowly operating the motorized valves in the box (the additional valves you refer to). Allowing full capacity to all other indoors when a box changes mode.
The outdoor also has independent heat exchanger control which only allows 1 heat exchanger to carry out a defrost cycle while the other continues to operate as an evaporator. The unit can then continue supplying hot gas to indoors, resulting in reduced capacity loss during defrosts cycle.

P.S. Have you changed your problem box yet? Did it cure the noise?