daikin outdoor unit connected to field supply indoor unit

hi got a daikin outdoor inverter 14 kw 410. connected to a invisible air indoor mini duct system. problem is its not cooling . 18 degrees at outlets. ive checked suction presure was at 70 psi so added 410. suction doesnt sweet back head pressure is low 225 psi. checked on heating works fine. I think its reversing valve. as there is a temperature diff on both suction pipes in and out. what are your thought

Adding refrigerant to an inverter system because you don't recognise the operating pressure is not the correct way to go.

If you thought that it was short of gas then you should weigh out the charge to establish whether it was short or not.

If it was short then you should check for any leaks, if any then fix them before weighing in the correct charge.