WP#10080 TJ Shaffer, C Compton. 10:30am -12:30pm
Today we swapped the spare CO2 chiller (S/N 813) with the TCSY chiller (S/N 617). This is to check the spare chiller is functioning correctly so that we have a fully functioning spare going into O4- alog 60547.
Will plan to leave the spare chiller circulating for ~2 weeks before swapping back if no problems are seen. It is expected the spare chiller may have temperature or flow rate fluctuations which is fine for keeping water circulating now but problematic in future when running the CO2 laser.
Steps taken:
- Wiped inside of spare chiller with non-lifting cloths.
- Turned off and unplugged TCS CO2Y chiller
- Flushed spare chiller with lab water (should be done if the chiller is stored for more than 90 days). See instructions below*.
- Disconnected TCS CO2Y hose quick connects to remove the chiller from the water system- note on the chiller side these aren’t dry breaks so we used out shorting hose to stop the chiller leaking.
- Connected outlet of spare chiller to water line, filled reservoir and connected inlet to water line.
- Turned on chiller and returned settings to the nominal “serial communications” = RS235 for MEDM control.
- Drained TCSY chiller - this drained very slowly. Have left drain value open. Will be left for 2 weeks max so didn’t vacuum out.
The amount of water drained from each chiller was ~ 2 gallons.
*Chiller flush instructions:
Followed some of the instructions in T1600050 which describe flushing chillers PLUS lines
- Shorted process inlet and outlet together with a piece of short pipe (photo).
- Filled up reservoir and shorting pipe with lab water (pre-filling prep makes less low pressure alarms as the chiller has water to suck in)
- Plugged in and turned on chiller
- Changed “serial communications” setting from RS235(?) to OFF temporarily so chiller doesn’t require medm to turn on.
- Turned on chiller and let water recirculate for a few minutes though all the pipes (inlet/outlet and internal recirculation pipe) by switching the yellow lever.
- Turned chiller off, unplugged.
- Drained chiller by opening drain value and directing water with hose into a bucket (photo).
- Changed metal mesh diffuser and mesh bag to new ones. The old ones were a little green.
Looking at the trends attached the spare chiller is functioning fine. It seems more stable thant he current CO2X chiller. It has a few flow drops down to 1.5gpm but these only last one data point (5 seconds). This will not trip the laser. See alog 58314 when the laser was still running with a very varying flow meter reading.
We plan to swap this chiller back in the new year.
