Since last Tuesday a 1Hz comb noise was present the CEB magnetometers and UPS probes. This reminded us of the TCS chiller noise. Indeed on Nov 14 the broken WI chiller was replaced with the spare. Today at 14:20 UTC Lorenzo set the WI CO2 laser chiller "power save mode", the noise removed: Figure 1.
Figure 2 shows the impact of the noise on SSFS and Hrec signals.