Reports until 20:45, Sunday 07 June 2015
LHO FMCS
john.worden@LIGO.ORG - posted 20:45, Sunday 07 June 2015 - last comment - 05:31, Monday 08 June 2015(18963)
LVEA Temperature control

It appears that the LVEA temperature is out of control. After consulting with Jim we decided to turn off a heater in the LVEA air handlers. This should bring the face bypass damper back in range.

HC2B was turned off. One heater, HC3A, remains on and will be turned off on Tuesday if tonight's change goes smoothly.

Plots show the LVEA temperature and the dampers which control airflow over the cooling coils. The dampers have railed the last two days in this hot weather.

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john.worden@LIGO.ORG - 05:31, Monday 08 June 2015 (18970)

The recovery from turning off one LVEA heater is shown.  The zoom-in shows a 2 hour ramp down to the minimum - a change of ~0.7F degrees. The individual zone temperatures do not appear to have such a steep ramp.

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