got a Daikin vrv 410a which has a strange problem.

on first startup the reversing valve doesn't seem quite to have the pressure difference to kick over and gets stuck in the midway position. this sends hot gas straight into the suction line and as the inverter ramps up causes it to trip on high temp.

If I press the other two non inv's comps contactors it swaps over and holds. once away the system runs 'normally'

I now know that the system is undercharged but by only 5-8kg out of 25-28kg charge.

I wonder if anyone knows of this as it's got more than a few perplexed.

I shall be returning next week to add the final charge but in the meantime welcome any thoughts..like is the inverter ramping up sufficiently at first start up??

cheers

richard