Help with walk-in cold room and Freezer

Good morning from Thailand.

I am a OLD A/C refrigeration tech, over 20 years ago.
I have a customer that has 2 Walk in's a cold room and a freezer.
I won't go into the history, but one doesn't work and 1 only operates with a low R-22 charge.
There is an electric Valve in the liquid line on the outside of the building where the tubing enter the building.
There is a IR33COHBOO controller in a control box outside the walk in door.
The condensing unit is on the roof about 6 feet above the evaporator the tubing length is about 18 feet.
The condensing unit is directly in the sun 12 hours a day. Average air temperature here is 34C
humidity 80%.

Every so called technician has had a go at the systems in the last 2 years, they never worked properly or for long since they were installed5 years ago, and all components have a 2006 date on them, there is no wiring diagram.

I can not find the manual for the IR33COHBOO controller.

As usual here in Asia no name, no drawings, no marking, just the supplier and he has no information, to old.

I have committed to get the system running.

Any help would be appreciated.

Thanks