FV glycol jackets not cooling? Solutions?

[SDDanC]

It appears as if one of our 15 bbl cylindroconicals might not be responding to the temperature control. Temperature reading is at 87 degrees F and for the past 10 hours the glycol control has been set at 61 degrees F. There is currently beer fermenting (day one) in the tank. As the temperature continues to creep skyward, I start getting nervous. What are some solutions? (Besides having system eval'ed and repaired if necessary- that appt is already scheduled). Looking for suggestions on what to do while waiting for service.

Cheers!

[DancingCamel]

Cone jackets?

Is it a full batch? If not and you don't have two zones with a jacket in the cone then your beer may not be reaching the level of the jacket.

[Matt Dog]

Is it a new tank just brought on line? Could be air-locked and need to be purged of air/flushed with glycol. Solenoid could be stuck or not powered. Can you hear the solenoid energizing?

[Starcat]

Tests

Disconnect your return hose [s] , open the control solenoid and observe the flow into a bucket or the like. You have to verify you are getting cooling through the jackets as a first step. We have one style [brand ] of tank that would make you think its not performing, but rather its heat transfer performance is very weak compared to another MFG. It exhibits very slow pulldown with no flow restriction through the jackets. Jackets can be tested by MFG. specs for GPM with the above method if you have a figure.
There are stories of jackets having been collapsed by incorrect usage and thermal shock etc.

[SDDanC]

After a few days of trying to troubleshoot it was found that the solenoids were not engaging and required a manual open. After manually opening, the glycol began cooling the tank but is still not responding to temperature settings from the control panel. Unfortunately I was not present when these valves were adjusted, so I am not certain whether it was malpractice or something in our circuitry causing the faulty cooling.

[Starcat]

Control Outputs

The controller serves to
1. Read out tank tamperature
2. Actuate cooling on generally a 2 degree differential from setpoint
Both controllers and sensors can fail. Failed temp sensors can cause different problems depending on the control, causing fail open or closed fault on the control output. If there is no voltage at the glycol solenoid, then the controller is not outputting or there is a loose connection in the chain. If there is proper voltage at the solenoid coil, then the coil has failed open.