Oil flow switch closed

[adulind]

hi,
my 450T trane chiller kicked out and will not restart. the code on the panel is A72, bE8 which means that the oil flow switch is closed. we changed the oil filter and got it going but it kicked out again after running briefly. in the afternoon, the cooling tower water coming in was as low as 56 deg F. i heated it up to about 62 deg F, but the chiller would still not reset.

what incoming cooling tower temp is ideal?
what else could be responsible for the oil flow switch closed alarm other than the switch not working right?

please help!

 

[wzal]

Is there a sight glass you can use to check the oil level?
Throttling the water valve on the cooling water loop, you will be able to raise the condening pressure and let the chiller run warmer.
Good luck!

 

[CESSNA1]

ADULIND: The switch could also be defective.

Regards
Dave