461pat, find and read the IOM for this unit. If I remember right, a new unit in cooling mode should have 11-14 deg F rise across the source side piping and 8-10 deg F drop in heating mode. This must be established first.
If you can't get these numbers by adjusting the source side balancing valve, you need to verify there is correct water flow (see the IOM for GPM requirements). After that check for refrigerant leaks 'cause those pressures you posted are low.
I think the McQuay control board is cycling the RV to prevent the source side coil from freezing and splitting.
When it's appropriate, remind your customer about safe access to their equipment. Who suffers when you're dangling from your now broken wrist which was wiggled throught the sprinkler lines as the Water Bottle Co. takes out your ladder with his 2-wheel dolly? Stand up for yourself, stand up for all of us. That's BS.