(I forgot to upload this on k-log...)
On the last Friday (2021/07/30), Kenta found the glitchly behavior on the PMC heater. Channel name is K1:PSL-PMC_HEATER_INMON . The time is around 10:20 JST. (see the attached figure) In six hours, the signal came back to usual value. Although I checked the microphones around 10:20, I could not find the coincident signal.
For future checking, I added the time-series of this channel on summary page.