Hi,
Im currently commissioning x2 114kW bespoke air cooled AC units and I'm trying to work out the correct staging setpoints for the twin scrolls. The setup is that the unit has x2 circuits and each circuit has x2 twin scrolls Model: ZR144KCE-TFD-455 with common oil balancing lines between the two compressors. They are staging the compressors and the main setpoint off supply air temperature which is causing it to short cycle.

Configuration is:
Circuit 1 Compressor 1
Circuit 1 Compressor 2
Circuit 2 Compressor 1
Circuit 2 Compressor 2

So I have a few questions about the setup:
1. How should the compressors stage up? I would usually expect them to be C1,C2,C3,C4 but after trending the temperature today we found it to be more stable as C1,C3,C2,C4. Is it ok to have this configuration and run x1 compressor on each circuit. Will this cause any issues with oil return because of the reduction in mass flow rate of the refrigerant?

2. What is the recommended staging ON/OFF setpoints for the compressors?

If we cannot stabilise the cycling of compressors then I will probably recommend changing it to return air temperature control.

Can you recommend any documentation I can read on this?

Thanks in advance