Chiller Not Cooling Properly

Issue

The chiller is not cooling down to the set point which by default is 20 degrees C

Environment

• ThermoFlex 900
• ThermoFlex 1400
• ThermoFlex 2500

Resolution

1. Ensure the chiller is situated in a way to allow proper heat dissipatation by reviewing page 10 (PDF #20) of the Thermo Flex Operators manual linked here:  U00933 - Rev. 06/01/07 - ThermoFlex Installation, Operation and Basic Maintenance

2. Clean the air filter by following page 44 (PDF #54) of the ThermoFlex Operators manual linked here: U00933 - Rev. 06/01/07 - ThermoFlex Installation, Operation and Basic Maintenance

For air cooled units, continue to  step 3. For water cooled units, continue to step 5.

3. Confirm the condenser fan is working. A easy way to check this is to hold a piece of paper over the front grill. If it is pulled into the unit, the fan motor is working. If not, this may mean that the fan is not working and needs to be replaced. If the fan motor has seized and the fan is therefore not working, a box fan can be place in front of the unit to provide airflow across the condenser coils. This can help to keep the chiller operational until a replacement fan motor can be installed. 

4. Clean the condenser coil

a. Power off the chiller using the rocker switch on the rear of the chiller and unplug it from the wall outlet

b. Remove the air filter by gently prying it away from the chiller itself

Note: The condenser framing and fins located behind the air filter assembly are very sharp, so use caution when working in this area.

d. Inspect the condenser fins  and use a vacuum with a soft-bristle brush attachment to gently remove any loose dirt or debris. An alternative would be to use a soft bristle brush along with vacuum to remove the loose dirt or debris.

Note: Be careful not to bend or damage the delicate fins of the coil.

If no vacuum is available, compressed air can be used to blow out any potential dry dust or debris. 

Note: Compressed air should only be used if the unit can be moved outside as it will cause dust and debris to circulate within the room.

If this does not resolve the issue continue to step 6.

5. Ensure the facility water meets the temperature and flow rate per the facility water requirements section of the manual.

If this does not resolve the issue, continue to step 6.

6. Use the knowledge article linked here: Improper Shutdown Procedure for the Stepper Valve to try and reset the stepper valve

 

Analysis

A dirty air filter or condenser coil can block air flow and reduce the chiller's capability to cool