This code can hold this chiller from running. A good way to check the temperatures on the waterside is by laser probe or temperature clamp. You can verify the temperature reading with the temperature within the Comfort Link.

Use the following steps to verify the temperature reading:

1. Go into the comfort link panel under “Temperature”.
2. It will show “Unit” > Hit enter > EWT (Entering Water Temperature) is displayed > Scroll down once to show the LWT (Leaving Water Temperature). This will show what both sensors are reading.
3. If they are off, then you have a bad thermistor.

If it happens on the leaving water of the chiller, the chiller will not run for more than 5 minutes. This is because with a bad LWT the system will not process that it’s cooling.

When this happens, you can use the outside air thermistor. They are mounted on top of the control panel box. Verify that the temperature is reading correctly to outside conditions. You can swap this with your leaving water temperature thermistor to get the machine back online. The only catch is to make sure the bad thermistor is not reading cold. If it reads under 35 degrees, the chiller will not start.

This is not a permanent fix, but this will get the machine online. This can be used as well for bad suction transducers if the need comes up.