Got a YVAA trowing up high base plate temps the last couple months. The coolant pump was changed last year as was the coolant.

Running system # 1 yesterday, it is hitting 98 DegC and 115 Hz approx. System # 2 is about 20 DegC lower when it is running also with system # 1. Shut it down and check for coolant level and it is down at the bottom of the filler tube. Top it up to about 12 inches below the top and run the pump in service mode for 20 minutes or so. Check the level and it’s good.

Restarted the chiller and still have the same issue. All fans running and coolant coils clean.
Coolant in temp to the coolant coils is about 30 DegC and dropping to about 22 DegC on the outlet.

I am getting that 22 DegC into the base plate and picking up 6 or 7 DegC so there is heat exchange. The coolant coils are the old micro channel coils. While on site yesterday I got to run system # 2 only to about 120 Hz and T2 temp went to and stayed around 65 DegC. I have seen that before so I would be happy enough with it.

I will be back on site next week and run system # 1 again, but I think its the problem system. I am leaning toward changing out the coils for the copper coils as per the retrofit SI. There has only ever been the York coolant used in this Chiller. I am thinking that the coils are blocked up or coil 1 at least and restricting my flow.

Cabinet temperature is around 26 DegC and ambient around 14 DegC. Just wondering if anyone has come across this before and did changing out the coils solve the issue?