I have a Trane RTWA 090 locking out Circuits A and B on high pressure. It has a single Belimo water regulating valve on the condenser water. I replaced the transformer which was way undersized, but it has tripped again.
The Belimo condenser water valve is controlled by Johnson Contols System 450. Basically, it measures the discharge pressure on both compressors, and then sends a 0-10VDC signal to my Belimo valve to maintain a pressure around 200.
When I reset the Chiller, both compressors run perfect. The discharge will be 190-200, 95-100 saturated condenser temp, 70-75 suction. Superheat 5-6, everything checks out.
Has anyone had trouble with a single water regulating valve on a two circuit system?
the 2nd RTWA090 has had no issues, but it runs with two regulating valves with cap tubes, rather than the single Belimo/Johnson controller.
The transducers piggyback to the same terminals on the Johnson Control.
Temporarily, I set the valve manually and unhooked the 24V power supply to the Belimo valve to verify I'm on the right track.
Can someone explain any potential issues, or what may be happening with my setup?
My theory is, when it starts to unload, something happens and the condenser water regulating valve shuts. JC, may be set incorrectly, or it may be a flawed design?